Wednesday, 22 July 2020

Mapping Mountains – Hill Reclassifications – The 500-Metre Tops of England and Wales – Deweys



The 500-Metre Tops of England and Wales – Deweys – Hill Reclassifications

The 500-Metre Tops of England and Wales are affectionately known after their hill list compiler; Michael Dewey.  This list mixes metric and imperial height in its criteria to bookend up to the 2000ft height band and takes in all hills in England, Isle of Man and Wales that are 500m and above and below 2000ft (609.6m) in height that have 30m minimum drop.

This list was first published in 1995 and formed one of many lists that appeared in the Mountain tables book published by Constable.  At the time of publication 373 hills were listed with 164 in England, 5 in the Isle of Man and 204 in Wales.

The Deweys have undergone extensive revision since first publication with over 90 reclassifications to the list.  Many people have contributed toward these, however there are only five people associated with ten or more reclassifications; Myrddyn Phillips, David Purchase, Rob Woodall, John Barnard and Graham Jackson.

The posts that have appeared on Mapping Mountains detailing the hill reclassifications specifically for this list appear below presented chronologically in receding order.








Mapping Mountains - Hill Reclassifications - The 500-Metre Tops of England and Wales - Deweys

Woldside (SD 874 830) – Dewey addition (35th reclassification)


This is one in a series of retrospective Hill Reclassification posts that detail hills whose status has altered in the listing of the Deweys and where I have had direct association with the status change.  These posts will tie in with a forthcoming Change Register giving detail to this list and its alterations since publication in the Mountain tables book.

LIDAR image of Woldside (SD 874 830)

The 500-Metre Tops of England and Wales are affectionately known after their hill list compiler; Michael Dewey.  This list mixes metric and imperial height in its criteria to bookend up to the 2000ft height band and takes in all hills in England, Isle of Man and Wales that are 500m and above and below 2000ft (609.6m) in height that have 30m minimum drop.

This list formed one of a number of lists that appeared in the Mountain tables book published by Constable in 1995 and at the time of publication comprised 373 hills with 164 in England, 5 in the Isle of Man and 204 in Wales.  The Deweys have undergone extensive revision since first publication with the initial stages forming the basis of this revision given below:


1995    Mountain tables published by Constable with 373 hills listed as Deweys.

April 2000    Strider (LDWA quarterly booklet) publishes contact details for David Purchase and Myrddyn Phillips who have found and list 24 and 14 possible new 500m tops respectively.

It was expanded versions of the above two lists that formed the basis of the next publication:

25th May 2000    List of Possible 500 Metre Tops by Michael Dewey listing 44 hills.

David Purchase expands his Additional Dewey 500m Hills and Myrddyn Phillips produces lists of English 500m hills to measure and Welsh 500m hills to measure.

These lists formed the basis of the next publication:

29th June 2000    Possible/Probable 500’s by Michael Dewey listing 77 hills.  Michael adopts following protocol; if one person proposes that a top should qualify as a 500 by personal survey, and is then confirmed by a second person, it should then be promoted to the main list.

April 2002    The 500+ Tops of England and Wales – The ‘New Deweys’ published in the Strider booklet and listing 66 new qualifying hills.

25th May 2006    Rob Woodall republishes Michael’s main and possible/probable lists on the RHB Yahoo group file database. 

Mountain tables by Michael Dewey

The details for this addition appear below:

The name the hill is listed by in the Deweys is Woldside, and it is adjoined to the Ingleborough group of hills which are situated in the Yorkshire Dales in England, and it is positioned with the A684 road to its north, the B6255 road to its west and the B6160 road to its east, and has the town of Hawes towards the north.

This hill was not included in the original 1995 Constable publication, but with a 596m summit spot height and col contouring between 560m – 570m that appear on the Ordnance Survey 1:25,000 Explorer map, the interpolated drop value was estimated sufficient for this hill to be a potential new Dewey.

Extract from the Ordnance Survey 1:25,000 Explorer map

The above detail was noted by Rob Woodall and Myrddyn Phillips who worked independently but also exchanged all data, with Rob having assessed the hill’s qualification on site.  These details were forwarded to the list author; Michael Dewey and the hill was added to the list on the 19th November 2000.

However, it was not until LIDAR became available that the details for this hill could be accurately re-assessed.  The LIDAR (Light Detection & Ranging) technique produced highly accurate height data that is now freely available for much of England and Wales.

LIDAR summit image for Woldside

LIDAR col image for Woldside

The summit and col heights for this hill were subsequently ascertained from LIDAR analysis conducted by Myrddyn Phillips, resulting in a 595.3m summit height and a 560.4m col height, with these values giving this hill 34.9m of drop, confirming its Dewey status. 


The full details for the hill are:

Name:  Woldside

OS 1:50,000 map:  98

OS 1:25,000 map:  2, 30

Summit Height:  595.3m (LIDAR)

Summit Grid Reference:  SD 87423 83003 and SD 87437 83001 (LIDAR)

Col Height:  560.4m (LIDAR)

Col Grid Reference:  SD 86487 83567 (LIDAR)

Drop:  34.9m (LIDAR)


Myrddyn Phillips (July 2020)







Mapping Mountains - Hill Reclassifications - The 500-Metre Tops of England and Wales - Deweys

Lowthwaite Fell (NY 278 347) – Dewey addition (34th reclassification)


This is one in a series of retrospective Hill Reclassification posts that detail hills whose status has altered in the listing of the Deweys and where I have had direct association with the status change.  These posts will tie in with a forthcoming Change Register giving detail to this list and its alterations since publication in the Mountain tables book.

The 500-Metre Tops of England and Wales are affectionately known after their hill list compiler; Michael Dewey.  This list mixes metric and imperial height in its criteria to bookend up to the 2000ft height band and takes in all hills in England, Isle of Man and Wales that are 500m and above and below 2000ft (609.6m) in height that have 30m minimum drop.

This list formed one of a number of lists that appeared in the Mountain tables book published by Constable in 1995 and at the time of publication comprised 373 hills with 164 in England, 5 in the Isle of Man and 204 in Wales.  The Deweys have undergone extensive revision since first publication with the initial stages forming the basis of this revision given below:


1995    Mountain tables published by Constable with 373 hills listed as Deweys.

April 2000    Strider (LDWA quarterly booklet) publishes contact details for David Purchase and Myrddyn Phillips who have found and list 24 and 14 possible new 500m tops respectively.

It was expanded versions of the above two lists that formed the basis of the next publication:

25th May 2000    List of Possible 500 Metre Tops by Michael Dewey listing 44 hills.

David Purchase expands his Additional Dewey 500m Hills and Myrddyn Phillips produces lists of English 500m hills to measure and Welsh 500m hills to measure.

These lists formed the basis of the next publication:

29th June 2000    Possible/Probable 500’s by Michael Dewey listing 77 hills.  Michael adopts following protocol; if one person proposes that a top should qualify as a 500 by personal survey, and is then confirmed by a second person, it should then be promoted to the main list.

April 2002    The 500+ Tops of England and Wales – The ‘New Deweys’ published in the Strider booklet and listing 66 new qualifying hills.

25th May 2006    Rob Woodall republishes Michael’s main and possible/probable lists on the RHB Yahoo group file database. 


Mountain tables by Michael Dewey

The details for this addition appear below:

The name the hill is listed by in the Deweys is Lowthwaite Fell, and it is adjoined to the Skiddaw group of hills which are situated in the Lake District in England, and it is positioned with the B5299 road to its north, the A591 road to its west and the A66 road to its south, and has the town of Keswick towards the south.

This hill was not included in the original 1995 Constable publication, but with a 509m summit spot height and col contouring between 470m – 480m that appear on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map, the interpolated drop value was estimated sufficient for this hill to be a potential new Dewey.

Extract from the Ordnance Survey 1:25,000 Explorer map

The above was noted by David Purchase and Myrddyn Phillips who worked independently but also exchanged all data.  These details were forwarded to the list author; Michael Dewey and the hill was added to the list on the 7th August 2000.

The full details for the hill are:

Name:  Lowthwaite Fell

OS 1:50,000 map:  89, 90

OS 1:25,000 map:  4

Summit Height:  509m (spot height)

Summit Grid Reference:  NY 27835 34746 (hand-held GPS via DoBIH)

Col Height:  c 478 (interpolation)

Col Grid Reference:  NY 28153 34513 (interpolation)

Drop:  c 31m (spot height summit and interpolated col)


Myrddyn Phillips (July 2020)







Mapping Mountains - Hill Reclassifications - The 500-Metre Tops of England and Wales - Deweys

Esgair y Maesnant (SN 832 862) – Dewey deletion (33rd reclassification)


This is one in a series of retrospective Hill Reclassification posts that detail hills whose status has altered in the listing of the Deweys and where I have had direct association with the status change.  These posts will tie in with a forthcoming Change Register giving detail to this list and its alterations since publication in the Mountain tables book.

The summit of Esgair y Maesnant (SN 832 862)

The 500-Metre Tops of England and Wales are affectionately known after their hill list compiler; Michael Dewey.  This list mixes metric and imperial height in its criteria to bookend up to the 2000ft height band and takes in all hills in England, Isle of Man and Wales that are 500m and above and below 2000ft (609.6m) in height that have 30m minimum drop.

This list formed one of a number of lists that appeared in the Mountain tables book published by Constable in 1995 and at the time of publication comprised 373 hills with 164 in England, 5 in the Isle of Man and 204 in Wales.  The Deweys have undergone extensive revision since first publication with the initial stages forming the basis of this revision given below:


1995    Mountain tables published by Constable with 373 hills listed as Deweys.

April 2000    Strider (LDWA quarterly booklet) publishes contact details for David Purchase and Myrddyn Phillips who have found and list 24 and 14 possible new 500m tops respectively.

It was expanded versions of the above two lists that formed the basis of the next publication:

25th May 2000    List of Possible 500 Metre Tops by Michael Dewey listing 44 hills.

David Purchase expands his Additional Dewey 500m Hills and Myrddyn Phillips produces lists of English 500m hills to measure and Welsh 500m hills to measure.

These lists formed the basis of the next publication:

29th June 2000    Possible/Probable 500’s by Michael Dewey listing 77 hills.  Michael adopts following protocol; if one person proposes that a top should qualify as a 500 by personal survey, and is then confirmed by a second person, it should then be promoted to the main list.

April 2002    The 500+ Tops of England and Wales – The ‘New Deweys’ published in the Strider booklet and listing 66 new qualifying hills.

25th May 2006    Rob Woodall republishes Michael’s main and possible/probable lists on the RHB Yahoo group file database. 


Mountain tables by Michael Dewey

The details for this addition appear below:

The name the hill was listed by in the Deweys is Esgair y Maesnant, and it is adjoined to the Pumlumon group of hills which are situated in the central part of Wales, and it is positioned with the A44 road to its south, and has the town of Llanidloes towards the east.

This hill was not included in the original 1995 Constable publication, but with a 504m summit spot height and bwlch contouring between 470m – 480m that appear on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map, this hill was noted as an outside possibility for a potential new Dewey.

Extract from the Ordnance Survey 1:25,000 Explorer map

The above detail was noted by Myrddyn Phillips who then conducted a basic levelling survey (BLS) of this hill on the 11th July 2000, resulting in 95½ft / 29.1m of drop.  These details were forwarded to the list author; Michael Dewey along with other recent results produced from basic levelling surveys.

Although surveyed as having less than the minimum 30m of drop required to enter this list, the hill was inadvertently included by Michael Dewey.  Its inclusion was subsequently noted during proof reading when an updated copy of the list was received by Myrddyn Phillips.  This hill’s deletion from Dewey status was confirmed in a letter received from the author dated 7th August 2000.  Although its inclusion in this list was an error, it was for a short period of time listed as a Dewey and therefore the details of this hill are appearing in this Hill Reclassification post and the forthcoming Change Register.

The Trimble GeoXH 6000 gathering data at the summit of Esgair y Maesnant

The Trimble GeoXH 6000 gathering data at the bwlch of Esgair y Maesnant

As the margin of uncertainty for the BLS method of surveying over terrain such as that on this hill is approximately +/- 2m and as the resulting 29.1m of drop was near the minimum 30m qualifying drop value, this hill was prioritised for a GNSS survey, and this took place on the 18th July 2016.  The summit and bwlch of this hill were surveyed by Myrddyn Phillips using a Trimble GeoXH 6000, resulting in a 503.6m summit height and a 476.2m bwlch height, with these values giving this hill 27.3m of drop, and confirming its non-Dewey status.


The full details for the hill are:

Name:  Esgair y Maesnant

OS 1:50,000 map:  135, 136

OS 1:25,000 map:  214

Summit Height:  503.6m (converted to OSGM15, Trimble GeoXH 6000)

Summit Grid Reference:  SN 83220 86275 (Trimble GeoXH 6000)

Bwlch Height:  476.2m (converted to OSGM15, Trimble GeoXH 6000)

Bwlch Grid Reference:  SN 82792 86427 (Trimble GeoXH 6000)

Drop:  27.3m (Trimble GeoXH 6000)


Myrddyn Phillips (July 2020)






Mapping Mountains - Hill Reclassifications - The 500-Metre Tops of England and Wales - Deweys

Foel Cynfal (SH 749 395) – Dewey deletion (32nd reclassification)


This is one in a series of retrospective Hill Reclassification posts that detail hills whose status has altered in the listing of the Deweys and where I have had direct association with the status change.  These posts will tie in with a forthcoming Change Register giving detail to this list and its alterations since publication in the Mountain tables book.

Foel Cynfal (SH 749 395)

The 500-Metre Tops of England and Wales are affectionately known after their hill list compiler; Michael Dewey.  This list mixes metric and imperial height in its criteria to bookend up to the 2000ft height band and takes in all hills in England, Isle of Man and Wales that are 500m and above and below 2000ft (609.6m) in height that have 30m minimum drop.

This list formed one of a number of lists that appeared in the Mountain tables book published by Constable in 1995 and at the time of publication comprised 373 hills with 164 in England, 5 in the Isle of Man and 204 in Wales.  The Deweys have undergone extensive revision since first publication with the initial stages forming the basis of this revision given below:


1995    Mountain tables published by Constable with 373 hills listed as Deweys.

April 2000    Strider (LDWA quarterly booklet) publishes contact details for David Purchase and Myrddyn Phillips who have found and list 24 and 14 possible new 500m tops respectively.

It was expanded versions of the above two lists that formed the basis of the next publication:

25th May 2000    List of Possible 500 Metre Tops by Michael Dewey listing 44 hills.

David Purchase expands his Additional Dewey 500m Hills and Myrddyn Phillips produces lists of English 500m hills to measure and Welsh 500m hills to measure.

These lists formed the basis of the next publication:

29th June 2000    Possible/Probable 500’s by Michael Dewey listing 77 hills.  Michael adopts following protocol; if one person proposes that a top should qualify as a 500 by personal survey, and is then confirmed by a second person, it should then be promoted to the main list.

April 2002    The 500+ Tops of England and Wales – The ‘New Deweys’ published in the Strider booklet and listing 66 new qualifying hills.

25th May 2006    Rob Woodall republishes Michael’s main and possible/probable lists on the RHB Yahoo group file database. 

Mountain tables by Michael Dewey

The details for this deletion appear below:

The name the hill was listed by in the Deweys is Foel Cynfal, and it is adjoined to the Arenig group of hills which are situated in the central part of North Wales, and it is positioned with the B4391 road to its north, the A470 road to its west and the A4212 road to its south, and has the village of Trawsfynydd towards the south-west.

This hill was not included in the original 1995 Constable publication, with no summit spot height on the publicly available Ordnance Survey maps and with an uppermost 540m ring contour and bwlch contouring between 510m – 520m that appear on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map, this hill was noted as an outside possibility for a potential new Dewey.

Extract from the Ordnance Survey 1:25,000 Explorer map

The above detail was noted by Myrddyn Phillips who then conducted a basic levelling survey (BLS) of this hill on the 15th July 2000, resulting in 93½ft / 28.5m of drop.  These details were forwarded to the list author; Michael Dewey along with other recent results produced from basic levelling surveys.

Although surveyed as having less than the minimum 30m of drop required to enter this list, the hill was inadvertently included by Michael Dewey.  Its inclusion was subsequently noted during proof reading when an updated copy of the list was received by Myrddyn Phillips.  This hill’s deletion from Dewey status was confirmed in a letter received from the author dated 7th August 2000.  Although its inclusion in this list was an error, it was for a short period of time listed as a Dewey and therefore the details of this hill are appearing in this Hill Reclassification post and the forthcoming Change Register.

The Trimble GeoXH 6000 gathering data at the summit of Foel Cynfal

The Trimble GeoXH 6000 gathering data at the bwlch of Foel Cynfal

As the margin of uncertainty for the BLS method of surveying over terrain such as that on this hill is approximately +/- 2m and as the resulting 28.5m of drop was near the minimum 30m qualifying drop value, this hill was prioritised for a GNSS survey, and this took place on the 1st July 2017.  The summit and bwlch of this hill were surveyed by Myrddyn Phillips and Aled Williams using a Trimble GeoXH 6000, resulting in a 545.5m summit height and a 517.4m bwlch height, with these values giving this hill 28.1m of drop, and confirming its non-Dewey status.


The full details for the hill are:

Name:  Foel Cynfal

OS 1:50,000 map:  124

OS 1:25,000 map:  18

Summit Height:  545.5m (converted to OSGM15, Trimble GeoXH 6000)

Summit Grid Reference:  SH 74998 39546 (Trimble GeoXH 6000)

Bwlch Height:  517.4m (converted to OSGM15, Trimble GeoXH 6000)

Bwlch Grid Reference:  SH 74884 39528 (Trimble GeoXH 6000)

Drop:  28.1m (Trimble GeoXH 6000)


Myrddyn Phillips (July 2020)






Mapping Mountains - Hill Reclassifications - The 500-Metre Tops of England and Wales - Deweys

Moel y Gyrafolen (SH 672 352) – Dewey addition (31st reclassification)


This is one in a series of retrospective Hill Reclassification posts that detail hills whose status has altered in the listing of the Deweys and where I have had direct association with the status change.  These posts will tie in with a forthcoming Change Register giving detail to this list and its alterations since publication in the Mountain tables book.

Moel y Gyrafolen (SH 672 352)

The 500-Metre Tops of England and Wales are affectionately known after their hill list compiler; Michael Dewey.  This list mixes metric and imperial height in its criteria to bookend up to the 2000ft height band and takes in all hills in England, Isle of Man and Wales that are 500m and above and below 2000ft (609.6m) in height that have 30m minimum drop.

This list formed one of a number of lists that appeared in the Mountain tables book published by Constable in 1995 and at the time of publication comprised 373 hills with 164 in England, 5 in the Isle of Man and 204 in Wales.  The Deweys have undergone extensive revision since first publication with the initial stages forming the basis of this revision given below:


1995    Mountain tables published by Constable with 373 hills listed as Deweys.

April 2000    Strider (LDWA quarterly booklet) publishes contact details for David Purchase and Myrddyn Phillips who have found and list 24 and 14 possible new 500m tops respectively.

It was expanded versions of the above two lists that formed the basis of the next publication:

25th May 2000    List of Possible 500 Metre Tops by Michael Dewey listing 44 hills.

David Purchase expands his Additional Dewey 500m Hills and Myrddyn Phillips produces lists of English 500m hills to measure and Welsh 500m hills to measure.

These lists formed the basis of the next publication:

29th June 2000    Possible/Probable 500’s by Michael Dewey listing 77 hills.  Michael adopts following protocol; if one person proposes that a top should qualify as a 500 by personal survey, and is then confirmed by a second person, it should then be promoted to the main list.

April 2002    The 500+ Tops of England and Wales – The ‘New Deweys’ published in the Strider booklet and listing 66 new qualifying hills.

25th May 2006    Rob Woodall republishes Michael’s main and possible/probable lists on the RHB Yahoo group file database. 


Mountain tables by Michael Dewey

The details for this addition appear below:

The name the hill is listed by in the Deweys is Moel y Gyrafolen, and it is adjoined to the Rhinogydd group of hills which are situated in the north-western part of Wales, and it is positioned with the A496 road to its west and the A470 road to its east, and has the village of Trawsfynydd towards the east.

This hill was not included in the original 1995 Constable publication, but with a 535m summit spot height and bwlch contouring between 500m – 510m that appear on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map, this hill was noted as an outside possibility for a potential new Dewey.

Extract from the Ordnance Survey 1:25,000 Explorer map

The above detail was noted by Myrddyn Phillips who then conducted a basic levelling survey (BLS) of this hill on the 23rd July 2000, resulting in 100ft / 30.5m of drop.  These details were forwarded to the list author; Michael Dewey and the hill was added to the list with the date of survey given in the Remarks column accompanying the list.

As the margin of uncertainty for the BLS method of surveying over terrain such as that on Moel y Gyrafolen is approximately +/- 1.5m and as the resulting 30.5m of drop was near the minimum 30m qualifying drop value, this hill was prioritised for a GNSS survey, and this took place on the 22nd February 2013.  The summit and bwlch of this hill were surveyed by John Barnard, Graham Jackson and Myrddyn Phillips using a Leica GS15.

Surveying for summit position on Moel y Gyrafolen

The Leica GS15 set-up position at the bwlch of Moel y Gyrafolen

The survey resulted in a 536.8m summit height and a 506.7m bwlch height, with these values giving this hill 30.1m of drop, and confirming its Dewey status.

The full details for the hill are:

Name:  Moel y Gyrafolen

OS 1:50,000 map:  124

OS 1:25,000 map:  18

Summit Height:  536.8m (converted to OSGM15, Leica GS15)

Summit Grid Reference:  SH 67218 35292 (Leica GS15)

Bwlch Height:  506.7m (converted to OSGM15, Leica GS15)

Bwlch Grid Reference:  SH 67066 35195 (Leica GS15)

Drop:  30.1m (Leica GS15)


Myrddyn Phillips (July 2020)







Mapping Mountains - Hill Reclassifications - The 500-Metre Tops of England and Wales - Deweys

Clip (SH 654 329) – Dewey addition (30th reclassification)


This is one in a series of retrospective Hill Reclassification posts that detail hills whose status has altered in the listing of the Deweys and where I have had direct association with the status change.  These posts will tie in with a forthcoming Change Register giving detail to this list and its alterations since publication in the Mountain tables book.

Clip (SH 654 329)

The 500-Metre Tops of England and Wales are affectionately known after their hill list compiler; Michael Dewey.  This list mixes metric and imperial height in its criteria to bookend up to the 2000ft height band and takes in all hills in England, Isle of Man and Wales that are 500m and above and below 2000ft (609.6m) in height that have 30m minimum drop.

This list formed one of a number of lists that appeared in the Mountain tables book published by Constable in 1995 and at the time of publication comprised 373 hills with 164 in England, 5 in the Isle of Man and 204 in Wales.  The Deweys have undergone extensive revision since first publication with the initial stages forming the basis of this revision given below:


1995    Mountain tables published by Constable with 373 hills listed as Deweys.

April 2000    Strider (LDWA quarterly booklet) publishes contact details for David Purchase and Myrddyn Phillips who have found and list 24 and 14 possible new 500m tops respectively.

It was expanded versions of the above two lists that formed the basis of the next publication:

25th May 2000    List of Possible 500 Metre Tops by Michael Dewey listing 44 hills.

David Purchase expands his Additional Dewey 500m Hills and Myrddyn Phillips produces lists of English 500m hills to measure and Welsh 500m hills to measure.

These lists formed the basis of the next publication:

29th June 2000    Possible/Probable 500’s by Michael Dewey listing 77 hills.  Michael adopts following protocol; if one person proposes that a top should qualify as a 500 by personal survey, and is then confirmed by a second person, it should then be promoted to the main list.

April 2002    The 500+ Tops of England and Wales – The ‘New Deweys’ published in the Strider booklet and listing 66 new qualifying hills.

25th May 2006    Rob Woodall republishes Michael’s main and possible/probable lists on the RHB Yahoo group file database. 


Mountain tables by Michael Dewey

The details for this addition appear below:

The name the hill is listed by in the Deweys is Clip, and it is adjoined to the Rhinogydd group of hills which are situated in the north-western part of Wales, and it is positioned with the A496 road to its west and the A470 road to its east, and has the village of Trawsfynydd towards the east north-east.

This hill was not included in the original 1995 Constable publication, but with an uppermost 590m ring contour and bwlch contouring between 560m – 570m that appear on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map, the interpolated drop value was estimated sufficient for this hill to be a potential new Dewey.

Extract from the Ordnance Survey 1:25,000 Explorer map

The above detail was noted by Myrddyn Phillips who then conducted a basic levelling survey (BLS) of this hill on the 23rd July 2000, resulting in 103ft / 31.4m of drop.  These details were forwarded to the list author; Michael Dewey and the hill was added to the list with the date of survey given in the Remarks column accompanying the list.

Since the inclusion of this hill in the Dewey list the Ordnance Survey Vector Map Local hosted on the Geograph website and which is entitled the Interactive Coverage Map became available online.  This mapping had many spot heights not on other publicly available Ordnance Survey maps and gives a 595m summit spot height and a 564m bwlch spot height for this hill, with these values giving 31m of drop.

Extract from the WalkLakes website

The 595m summit spot height also appears on the WalkLakes interactive map which is available online.  This map originated from the Ordnance Survey Open Data programme and has many spot heights not on other publicly available Ordnance Survey maps.

The Trimble GeoXH 6000 gathering data at the summit of Clip

The Trimble GeoXH 6000 gathering data at the bwlch of Clip

Although the margin of uncertainty for the BLS method of surveying over terrain such as that on this hill is not considered great and is approximately +/- 1m, and as the resulting 31.4m of drop was near the minimum 30m qualifying drop value, this hill was prioritised for a GNSS survey, and this took place on the 17th November 2018.  The summit and bwlch of this hill were surveyed by Myrddyn Phillips and Aled Williams using a Trimble GeoXH 6000, resulting in a 595.3m summit height and a 564.0m bwlch height, with these values giving this hill 31.3m of drop, and confirming its Dewey status.


The full details for the hill are:

Name:  Clip

OS 1:50,000 map:  124

OS 1:25,000 map:  18

Summit Height:  595.3m (converted to OSGM15, Trimble GeoXH 6000)

Summit Grid Reference:  SH 65460 32942 (Trimble GeoXH 6000)

Bwlch Height:  564.0m (converted to OSGM15, Trimble GeoXH 6000)

Bwlch Grid Reference:  SH 65551 32999 (Trimble GeoXH 6000)

Drop:  31.3m (Trimble GeoXH 6000)


Myrddyn Phillips (July 2020)







Mapping Mountains - Hill Reclassifications - The 500-Metre Tops of England and Wales - Deweys

Cripiau South Top (SN 802 828) – Dewey addition (29th reclassification)


This is one in a series of retrospective Hill Reclassification posts that detail hills whose status has altered in the listing of the Deweys and where I have had direct association with the status change.  These posts will tie in with a forthcoming Change Register giving detail to this list and its alterations since publication in the Mountain tables book.

The hill listed as Cripiau South Top (SN 802 828) in the Deweys

The 500-Metre Tops of England and Wales are affectionately known after their hill list compiler; Michael Dewey.  This list mixes metric and imperial height in its criteria to bookend up to the 2000ft height band and takes in all hills in England, Isle of Man and Wales that are 500m and above and below 2000ft (609.6m) in height that have 30m minimum drop.

This list formed one of a number of lists that appeared in the Mountain tables book published by Constable in 1995 and at the time of publication comprised 373 hills with 164 in England, 5 in the Isle of Man and 204 in Wales.  The Deweys have undergone extensive revision since first publication with the initial stages forming the basis of this revision given below:


1995    Mountain tables published by Constable with 373 hills listed as Deweys.

April 2000    Strider (LDWA quarterly booklet) publishes contact details for David Purchase and Myrddyn Phillips who have found and list 24 and 14 possible new 500m tops respectively.

It was expanded versions of the above two lists that formed the basis of the next publication:

25th May 2000    List of Possible 500 Metre Tops by Michael Dewey listing 44 hills.

David Purchase expands his Additional Dewey 500m Hills and Myrddyn Phillips produces lists of English 500m hills to measure and Welsh 500m hills to measure.

These lists formed the basis of the next publication:

29th June 2000    Possible/Probable 500’s by Michael Dewey listing 77 hills.  Michael adopts following protocol; if one person proposes that a top should qualify as a 500 by personal survey, and is then confirmed by a second person, it should then be promoted to the main list.

April 2002    The 500+ Tops of England and Wales – The ‘New Deweys’ published in the Strider booklet and listing 66 new qualifying hills.

25th May 2006    Rob Woodall republishes Michael’s main and possible/probable lists on the RHB Yahoo group file database. 

Mountain tables by Michael Dewey

The details for this addition appear below:

The name the hill is listed by in the Deweys is Cripiau South Top, and it is adjoined to the Rhayader group of hills which are situated in the western part of Wales, and it is positioned with the A44 road to its north, and has the town of Llanidloes towards the east.

The Name: Cripiau South Top is an invented and directional name based on this hill’s proximity to the adjacent and lower hill of Cripiau (SN 798 836).  The hill remains unnamed on contemporary Ordnance Survey maps.

This hill was not included in the original 1995 Constable publication, but with a 524m summit spot height and bwlch contouring between 490m – 500m that appear on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map, the interpolated drop value was estimated sufficient for this hill to be a potential new Dewey.

Extract from the Ordnance Survey 1:25,000 Explorer map

The above detail was noted by Myrddyn Phillips who then conducted a basic levelling survey (BLS) of this hill on the 22nd July 2000, resulting in 100ft / 30.5m of drop.  These details were forwarded to the list author; Michael Dewey and the hill was added to the list with the date of survey given in the Remarks column accompanying the list.

Testing conditions during the line survey

Graham Jackson at the summit of Cripiau South Top during the line survey

As the result from the BLS was near the minimum 30m qualifying drop value this hill was prioritised for a line survey which took place on the 19th February 2010 and which was conducted by Graham Jackson and Myrddyn Phillips, resulting in 30.6m of drop; confirming this hill’s Dewey status.

The Trimble GeoXH 6000 gathering data at the summit of Cripiau South Top

This hill was subsequently surveyed using a GNSS receiver, and this took place on the 1oth April 2019.  The summit and bwlch of this hill were surveyed by Myrddyn Phillips using a Trimble GeoXH 6000, resulting in a 525.6m summit height and a 495.0m bwlch height, with these values giving this hill 30.6m of drop.


The full details for the hill are:

Name:  Cripiau South Top

OS 1:50,000 map:  135, 136

OS 1:25,000 map:  213, 214

Summit Height:  525.6m (converted to OSGM15, Trimble GeoXH 6000)

Summit Grid Reference:  SN 80202 82864 (Trimble GeoXH 6000)

Bwlch Height:  495.0m (converted to OSGM15, Trimble GeoXH 6000)

Bwlch Grid Reference:  SN 80293 82632 (Trimble GeoXH 6000)

Drop:  30.6m (Trimble GeoXH 6000 and level and staff line survey)


Myrddyn Phillips (July 2020)






Mapping Mountains - Hill Reclassifications - The 500-Metre Tops of England and Wales - Deweys


THIS HILL HAS SUBSEQUENTLY BEEN DELETED FROM THE DEWEY LIST


Foel Cynfal (SH 749 395) – Dewey addition (28th reclassification)


This is one in a series of retrospective Hill Reclassification posts that detail hills whose status has altered in the listing of the Deweys and where I have had direct association with the status change.  These posts will tie in with a forthcoming Change Register giving detail to this list and its alterations since publication in the Mountain tables book.

Foel Cynfal (SH 749 395)

The 500-Metre Tops of England and Wales are affectionately known after their hill list compiler; Michael Dewey.  This list mixes metric and imperial height in its criteria to bookend up to the 2000ft height band and takes in all hills in England, Isle of Man and Wales that are 500m and above and below 2000ft (609.6m) in height that have 30m minimum drop.

This list formed one of a number of lists that appeared in the Mountain tables book published by Constable in 1995 and at the time of publication comprised 373 hills with 164 in England, 5 in the Isle of Man and 204 in Wales.  The Deweys have undergone extensive revision since first publication with the initial stages forming the basis of this revision given below:


1995    Mountain tables published by Constable with 373 hills listed as Deweys.

April 2000    Strider (LDWA quarterly booklet) publishes contact details for David Purchase and Myrddyn Phillips who have found and list 24 and 14 possible new 500m tops respectively.

It was expanded versions of the above two lists that formed the basis of the next publication:

25th May 2000    List of Possible 500 Metre Tops by Michael Dewey listing 44 hills.

David Purchase expands his Additional Dewey 500m Hills and Myrddyn Phillips produces lists of English 500m hills to measure and Welsh 500m hills to measure.

These lists formed the basis of the next publication:

29th June 2000    Possible/Probable 500’s by Michael Dewey listing 77 hills.  Michael adopts following protocol; if one person proposes that a top should qualify as a 500 by personal survey, and is then confirmed by a second person, it should then be promoted to the main list.

April 2002    The 500+ Tops of England and Wales – The ‘New Deweys’ published in the Strider booklet and listing 66 new qualifying hills.

25th May 2006    Rob Woodall republishes Michael’s main and possible/probable lists on the RHB Yahoo group file database. 


Mountain tables by Michael Dewey

The details for this addition appear below:

The name the hill is listed by in the Deweys is Foel Cynfal, and it is adjoined to the Arenig group of hills which are situated in the central part of North Wales, and it is positioned with the B4391 road to its north, the A470 road to its west and the A4212 road to its south, and has the village of Trawsfynydd towards the south-west.

This hill was not included in the original 1995 Constable publication, with no summit spot height on the publicly available Ordnance Survey maps and with an uppermost 540m ring contour and bwlch contouring between 510m – 520m that appear on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map, this hill was noted as an outside possibility for a potential new Dewey.

Extract from the Ordnance Survey 1:25,000 Explorer map

The above detail was noted by Myrddyn Phillips who then conducted a basic levelling survey (BLS) of this hill on the 15th July 2000, resulting in 93½ft / 28.5m of drop.  These details were forwarded to the list author; Michael Dewey along with other recent results produced from basic levelling surveys.

Although surveyed as having less than the minimum 30m of drop required to enter this list, the hill was inadvertently included by Michael Dewey.  Its inclusion was subsequently noted during proof reading when an updated copy of the list was received by Myrddyn Phillips.  Although its inclusion in this list was an error, it was for a short period of time listed as a Dewey and therefore the details of this hill are appearing in this Hill Reclassification post and the forthcoming Change Register.

The Trimble GeoXH 6000 gathering data at the summit of Foel Cynfal

The Trimble GeoXH 6000 gathering data at the bwlch of Foel Cynfal

As the margin of uncertainty for the BLS method of surveying over terrain such as that on this hill is approximately +/- 2m and as the resulting 28.5m of drop was near the minimum 30m qualifying drop value, this hill was prioritised for a GNSS survey, and this took place on the 1st July 2017.  The summit and bwlch of this hill were surveyed by Myrddyn Phillips and Aled Williams using a Trimble GeoXH 6000, resulting in a 545.5m summit height and a 517.4m bwlch height, with these values giving this hill 28.1m of drop, and confirming its non-Dewey status.


The full details for the hill are:

Name:  Foel Cynfal

OS 1:50,000 map:  124

OS 1:25,000 map:  18

Summit Height:  545.5m (converted to OSGM15, Trimble GeoXH 6000)

Summit Grid Reference:  SH 74998 39546 (Trimble GeoXH 6000)

Bwlch Height:  517.4m (converted to OSGM15, Trimble GeoXH 6000)

Bwlch Grid Reference:  SH 74884 39528 (Trimble GeoXH 6000)

Drop:  28.1m (Trimble GeoXH 6000)


Myrddyn Phillips (June 2020)







Mapping Mountains - Hill Reclassifications - The 500-Metre Tops of England and Wales - Deweys


THIS HILL HAS SUBSEQUENTLY BEEN DELETED FROM THE DEWEY LIST


Esgair y Maesnant (SN 832 862) – Dewey addition (27th reclassification)


This is one in a series of retrospective Hill Reclassification posts that detail hills whose status has altered in the listing of the Deweys and where I have had direct association with the status change.  These posts will tie in with a forthcoming Change Register giving detail to this list and its alterations since publication in the Mountain tables book.

The summit of Esgair y Maesnant (SN 832 862)

The 500-Metre Tops of England and Wales are affectionately known after their hill list compiler; Michael Dewey.  This list mixes metric and imperial height in its criteria to bookend up to the 2000ft height band and takes in all hills in England, Isle of Man and Wales that are 500m and above and below 2000ft (609.6m) in height that have 30m minimum drop.

This list formed one of a number of lists that appeared in the Mountain tables book published by Constable in 1995 and at the time of publication comprised 373 hills with 164 in England, 5 in the Isle of Man and 204 in Wales.  The Deweys have undergone extensive revision since first publication with the initial stages forming the basis of this revision given below:


1995    Mountain tables published by Constable with 373 hills listed as Deweys.

April 2000    Strider (LDWA quarterly booklet) publishes contact details for David Purchase and Myrddyn Phillips who have found and list 24 and 14 possible new 500m tops respectively.

It was expanded versions of the above two lists that formed the basis of the next publication:

25th May 2000    List of Possible 500 Metre Tops by Michael Dewey listing 44 hills.

David Purchase expands his Additional Dewey 500m Hills and Myrddyn Phillips produces lists of English 500m hills to measure and Welsh 500m hills to measure.

These lists formed the basis of the next publication:

29th June 2000    Possible/Probable 500’s by Michael Dewey listing 77 hills.  Michael adopts following protocol; if one person proposes that a top should qualify as a 500 by personal survey, and is then confirmed by a second person, it should then be promoted to the main list.

April 2002    The 500+ Tops of England and Wales – The ‘New Deweys’ published in the Strider booklet and listing 66 new qualifying hills.

25th May 2006    Rob Woodall republishes Michael’s main and possible/probable lists on the RHB Yahoo group file database.  

Mountain tables by Michael Dewey

The details for this addition appear below:

The name the hill is listed by in the Deweys is Esgair y Maesnant, and it is adjoined to the Pumlumon group of hills which are situated in the central part of Wales, and it is positioned with the A44 road to its south, and has the town of Llanidloes towards the east.

This hill was not included in the original 1995 Constable publication, but with a 504m summit spot height and bwlch contouring between 470m – 480m that appear on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map, this hill was noted as an outside possibility for a potential new Dewey.

Extract from the Ordnance Survey 1:25,000 Explorer map

The above detail was noted by Myrddyn Phillips who then conducted a basic levelling survey (BLS) of this hill on the 11th July 2000, resulting in 95½ft / 29.1m of drop.  These details were forwarded to the list author; Michael Dewey along with other recent results produced from basic levelling surveys.

Although surveyed as having less than the minimum 30m of drop required to enter this list, the hill was inadvertently included by Michael Dewey.  Its inclusion was subsequently noted during proof reading when an updated copy of the list was received by Myrddyn Phillips.  Although its inclusion in this list was an error, it was for a short period of time listed as a Dewey and therefore the details of this hill are appearing in this Hill Reclassification post and the forthcoming Change Register.

The Trimble GeoXH 6000 gathering data at the summit of Esgair y Maesnant

The Trimble GeoXH 6000 gathering data at the bwlch of Esgair y Maesnant

As the margin of uncertainty for the BLS method of surveying over terrain such as that on this hill is approximately +/- 2m and as the resulting 29.1m of drop was near the minimum 30m qualifying drop value, this hill was prioritised for a GNSS survey, and this took place on the 18th July 2016.  The summit and bwlch of this hill were surveyed by Myrddyn Phillips using a Trimble GeoXH 6000, resulting in a 503.6m summit height and a 476.2m bwlch height, with these values giving this hill 27.3m of drop, and confirming its non-Dewey status.


The full details for the hill are:

Name:  Esgair y Maesnant

OS 1:50,000 map:  135, 136

OS 1:25,000 map:  214

Summit Height:  503.6m (converted to OSGM15, Trimble GeoXH 6000)

Summit Grid Reference:  SN 83220 86275 (Trimble GeoXH 6000)

Bwlch Height:  476.2m (converted to OSGM15, Trimble GeoXH 6000)

Bwlch Grid Reference:  SN 82792 86427 (Trimble GeoXH 6000)

Drop:  27.3m (Trimble GeoXH 6000)


Myrddyn Phillips (June 2020)






Mapping Mountains - Hill Reclassifications - The 500-Metre Tops of England and Wales - Deweys


ADDED TO THE DEWEY LIST AS BRYN YR ŴYN (SN 839 925) WITH THE HIGHER QUALIFYING HILL NOW SUBSTANTIATED AS ESGAIR GREOLEN (SN 835 920)


Esgair Greolen (SN 835 920) – Dewey addition (26th reclassification)


This is one in a series of retrospective Hill Reclassification posts that detail hills whose status has altered in the listing of the Deweys and where I have had direct association with the status change.  These posts will tie in with a forthcoming Change Register giving detail to this list and its alterations since publication in the Mountain tables book.

Esgair Greolen (SN 835 920)

The 500-Metre Tops of England and Wales are affectionately known after their hill list compiler; Michael Dewey.  This list mixes metric and imperial height in its criteria to bookend up to the 2000ft height band and takes in all hills in England, Isle of Man and Wales that are 500m and above and below 2000ft (609.6m) in height that have 30m minimum drop.

This list formed one of a number of lists that appeared in the Mountain tables book published by Constable in 1995 and at the time of publication comprised 373 hills with 164 in England, 5 in the Isle of Man and 204 in Wales.  The Deweys have undergone extensive revision since first publication with the initial stages forming the basis of this revision given below:


1995    Mountain tables published by Constable with 373 hills listed as Deweys.

April 2000    Strider (LDWA quarterly booklet) publishes contact details for David Purchase and Myrddyn Phillips who have found and list 24 and 14 possible new 500m tops respectively.

It was expanded versions of the above two lists that formed the basis of the next publication:

25th May 2000    List of Possible 500 Metre Tops by Michael Dewey listing 44 hills.

David Purchase expands his Additional Dewey 500m Hills and Myrddyn Phillips produces lists of English 500m hills to measure and Welsh 500m hills to measure.

These lists formed the basis of the next publication:

29th June 2000    Possible/Probable 500’s by Michael Dewey listing 77 hills.  Michael adopts following protocol; if one person proposes that a top should qualify as a 500 by personal survey, and is then confirmed by a second person, it should then be promoted to the main list.

April 2002    The 500+ Tops of England and Wales – The ‘New Deweys’ published in the Strider booklet and listing 66 new qualifying hills.

25th May 2006    Rob Woodall republishes Michael’s main and possible/probable lists on the RHB Yahoo group file database. 


Mountain tables by Michael Dewey

The details for this addition appear below:

The name the hill is listed by in the Deweys is Esgair Greolen, and it is adjoined to the Pumlumon group of hills which are situated in the central part of Wales, and it is positioned with the A44 road to its south and the B4518 road to its east, and has the town of Machynlleth towards the north-west and Llanidloes towards the south-east.

This hill was not included in the original 1995 Constable publication, but with a small uppermost 500m ring contour and bwlch contouring between 470m – 480m that appear on the Ordnance Survey 1:25,000 Explorer map, this hill was noted as an outside possibility for a potential new Dewey.

Extract from the Ordnance Survey 1:25,000 Explorer map

The above detail was noted by Myrddyn Phillips who then conducted a basic levelling survey (BLS) of this hill on the 11th July 2000, resulting in 106½ft / 32.5m of drop, with Bryn yr Ŵyn (SN 839 925) surveyed as higher than Esgair Greolen (SN 835 920).  These details were forwarded to the list author; Michael Dewey and the hill was added to the list with the date of survey given in the Remarks column accompanying the list.

Gathering data at the summit of Esgair Greolen

Gathering data at the bwlch of Esgair Greolen

Gathering data at the summit of Bryn yr Ŵyn

As the margin of uncertainty for the BLS method of surveying over terrain such as that on this hill is approximately +/- 2m and as the resulting 32.5m of drop was near the minimum 30m qualifying drop value and as both summits only have a small uppermost 500m ring contour, this hill was prioritised for a GNSS survey, and this took place over two days; on the 5th and 13th May 2016.  The summit and bwlch of this hill were surveyed by Myrddyn Phillips using a Trimble GeoXH 6000, resulting in a 501.4m summit height for Esgair Greolen and a 499.9m summit height for Bryn yr Ŵyn and a 471.2m bwlch height, with these values giving Esgair Greolen 30.3m of drop and in the process relocating the qualifying hill to the higher summit and confirming its Dewey status.


The full details for the hill are:

Name:  Esgair Greolen

OS 1:50,000 map:  135, 136

OS 1:25,000 map:  214, 215

Summit Height:  501.4m (converted to OSGM15, Trimble GeoXH 6000)

Summit Grid Reference:  SN 83574 92022 (Trimble GeoXH 6000)

Bwlch Height:  471.2m (converted to OSGM15, Trimble GeoXH 6000)

Bwlch Grid Reference:  SN 83220 91901 (Trimble GeoXH 6000)

Drop:  30.3m (Trimble GeoXH 6000)


Myrddyn Phillips (June 2020)







Mapping Mountains - Hill Reclassifications - The 500-Metre Tops of England and Wales - Deweys

Esgair y Maesnant S.E. Top (SN 842 856) – Dewey addition (25th reclassification)


This is one in a series of retrospective Hill Reclassification posts that detail hills whose status has altered in the listing of the Deweys and where I have had direct association with the status change.  These posts will tie in with a forthcoming Change Register giving detail to this list and its alterations since publication in the Mountain tables book.

Esgair y Maesnant S.E. Top (SN 842 856)

The 500-Metre Tops of England and Wales are affectionately known after their hill list compiler; Michael Dewey.  This list mixes metric and imperial height in its criteria to bookend up to the 2000ft height band and takes in all hills in England, Isle of Man and Wales that are 500m and above and below 2000ft (609.6m) in height that have 30m minimum drop.

This list formed one of a number of lists that appeared in the Mountain tables book published by Constable in 1995 and at the time of publication comprised 373 hills with 164 in England, 5 in the Isle of Man and 204 in Wales.  The Deweys have undergone extensive revision since first publication with the initial stages forming the basis of this revision given below:


1995    Mountain tables published by Constable with 373 hills listed as Deweys.

April 2000    Strider (LDWA quarterly booklet) publishes contact details for David Purchase and Myrddyn Phillips who have found and list 24 and 14 possible new 500m tops respectively.

It was expanded versions of the above two lists that formed the basis of the next publication:

25th May 2000    List of Possible 500 Metre Tops by Michael Dewey listing 44 hills.

David Purchase expands his Additional Dewey 500m Hills and Myrddyn Phillips produces lists of English 500m hills to measure and Welsh 500m hills to measure.

These lists formed the basis of the next publication:

29th June 2000    Possible/Probable 500’s by Michael Dewey listing 77 hills.  Michael adopts following protocol; if one person proposes that a top should qualify as a 500 by personal survey, and is then confirmed by a second person, it should then be promoted to the main list.

April 2002    The 500+ Tops of England and Wales – The ‘New Deweys’ published in the Strider booklet and listing 66 new qualifying hills.

25th May 2006    Rob Woodall republishes Michael’s main and possible/probable lists on the RHB Yahoo group file database. 


Mountain tables by Michael Dewey

The details for this addition appear below:

The name the hill is listed by in the Deweys is Esgair y Maesnant S.E. Top, and it is adjoined to the Pumlumon group of hills which are situated in the central part of Wales, and it is positioned with the A44 road to its south, and has the town of Llanidloes towards the east.

The Name: Esgair y Maesnant S.E. Top is an invented and directional name based on this hill’s proximity to the adjacent and lower hill of Esgair y Maesnant (SN 832 862).  The hill is named on most Ordnance Survey maps outside of contemporary ones, and is also known locally as Tor Du.

This hill was not included in the original 1995 Constable publication, but with a 506m summit spot height and bwlch contouring between 470m – 480m that appear on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map, the interpolated drop value was estimated sufficient for this hill to be a potential new Dewey.

Extract from the Ordnance Survey 1:25,000 Explorer map

The above detail was noted by Myrddyn Phillips who then conducted a basic levelling survey (BLS) of this hill on the 11th July 2000, resulting in 100½ft / 30.6m of drop.  These details were forwarded to the list author; Michael Dewey and the hill was added to the list with the date of survey given in the Remarks column accompanying the list.

As the margin of uncertainty for the BLS method of surveying over terrain such as that on this hill is approximately +/- 2m and as the resulting 30.6m of drop was near the minimum 30m qualifying drop value, this hill was prioritised for a GNSS survey, and this took place on the 18th July 2016.  The summit and bwlch of this hill were surveyed by Myrddyn Phillips using a Trimble GeoXH 6000, resulting in a 505.6m summit height and a 472.4m bwlch height, with these values giving this hill 33.2m of drop.

The Trimble GeoXH 6000 gathering data at the summit of Esgair y Maesnant S.E. Top

The Trimble GeoXH 6000 set-up position at the bwlch of Esgair y Maesnant S.E. Top

However, since the Trimble GeoXH 6000 survey of this hill, LIDAR has become available.  The LIDAR (Light Detection & Ranging) technique produced highly accurate height data that is now freely available for much of England and Wales. 

LIDAR image of Esgair y Maesnant S.E. Top

The summit and bwlch heights for this hill have now been ascertained from LIDAR analysis initially conducted by Aled Williams and subsequently by Myrddyn Phillips, resulting in a 505.6m summit height and a 472.6m bwlch height, with the latter positioned at SN 83837 85962, which is approximately nine metres from the Trimble set-up position, as the LIDAR position is considered more accurate for that of the bwlch, it is this result that is prioritised for this hill.


The full details for the hill are:

Name:  Esgair y Maesnant S.E. Top

OS 1:50,000 map:  135, 136

OS 1:25,000 map:  214

Summit Height:  505.6m (converted to OSGM15, Trimble GeoXH 6000)

Summit Grid Reference:  SN 84268 85679 (Trimble GeoXH 6000)

Bwlch Height:  472.6m (LIDAR)

Bwlch Grid Reference:  SN 83837 85962 (LIDAR)

Drop:  33.0m (Trimble GeoXH 6000 summit and LIDAR bwlch)


Myrddyn Phillips (June 2020)






Mapping Mountains - Hill Reclassifications - The 500-Metre Tops of England and Wales - Deweys

Lledwyn Mawr (SH 904 287) – Dewey addition (24th reclassification)


This is one in a series of retrospective Hill Reclassification posts that detail hills whose status has altered in the listing of the Deweys and where I have had direct association with the status change.  These posts will tie in with a forthcoming Change Register giving detail to this list and its alterations since publication in the Mountain tables book. 

Lledwyn Mawr (SH 904 287)

The 500-Metre Tops of England and Wales are affectionately known after their hill list compiler; Michael Dewey.  This list mixes metric and imperial height in its criteria to bookend up to the 2000ft height band and takes in all hills in England, Isle of Man and Wales that are 500m and above and below 2000ft (609.6m) in height that have 30m minimum drop.

This list formed one of a number of lists that appeared in the Mountain tables book published by Constable in 1995 and at the time of publication comprised 373 hills with 164 in England, 5 in the Isle of Man and 204 in Wales.  The Deweys have undergone extensive revision since first publication with the initial stages forming the basis of this revision given below:


1995    Mountain tables published by Constable with 373 hills listed as Deweys.

April 2000    Strider (LDWA quarterly booklet) publishes contact details for David Purchase and Myrddyn Phillips who have found and list 24 and 14 possible new 500m tops respectively.

It was expanded versions of the above two lists that formed the basis of the next publication:

25th May 2000    List of Possible 500 Metre Tops by Michael Dewey listing 44 hills.

David Purchase expands his Additional Dewey 500m Hills and Myrddyn Phillips produces lists of English 500m hills to measure and Welsh 500m hills to measure.

These lists formed the basis of the next publication:

29th June 2000    Possible/Probable 500’s by Michael Dewey listing 77 hills.  Michael adopts following protocol; if one person proposes that a top should qualify as a 500 by personal survey, and is then confirmed by a second person, it should then be promoted to the main list.

April 2002    The 500+ Tops of England and Wales – The ‘New Deweys’ published in the Strider booklet and listing 66 new qualifying hills.

25th May 2006    Rob Woodall republishes Michael’s main and possible/probable lists on the RHB Yahoo group file database. 

Mountain tables by Michael Dewey

The details for this addition appear below:

The name the hill is listed by in the Deweys is Lledwyn Mawr, and it is adjoined to the Aran group of hills which are situated in the southern part of North Wales, and it is positioned with the B4403 road to its north, the A494 road to its west and the B4391 road to its east, and has the town of Y Bala towards the north north-east.

This hill was not included in the original 1995 Constable publication, but with a 527m summit spot height and bwlch contouring between 490m – 500m that appear on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map, the interpolated drop value was estimated sufficient for this hill to be a potential new Dewey.

Extract from the Ordnance Survey 1:25,000 Explorer map

The above detail was noted by David Purchase and Myrddyn Phillips who worked independently but also exchanged all data.  On the 7th July 2000 Myrddyn Phillips conducted a basic levelling survey (BLS) of this hill, resulting in 99½ft / 30.3m of drop.  These details were forwarded to the list author; Michael Dewey and the hill was added to the list with the date of survey given in the Remarks column accompanying the list.

As the margin of uncertainty for the BLS method of surveying over terrain such as that on Lledwyn Mawr is approximately +/- 1.5m and as the resulting 30.3m of drop was near the minimum 30m qualifying drop value, this hill was prioritised for a GNSS survey, and this took place on the 2nd and 8th February 2012.  The summit and bwlch of this hill were surveyed by John Barnard, Graham Jackson and Myrddyn Phillips using a Leica 530, with 60 minutes of data gathered at the summit and 90 minutes at the bwlch on the first day’s survey and 60 minutes at the bwlch on the second day’s survey.

Gathering data during the first bwlch survey

The survey resulted in a 526.1m summit height and a 495.1m bwlch height, with these values giving this hill 30.9m of drop, and confirmed this hill’s Dewey status. 


The full details for the hill are:

Name:  Lledwyn Mawr

OS 1:50,000 map:  125

OS 1:25,000 map:  23

Summit Height:  526.1m (converted to OSGM15, Leica 530)

Summit Grid Reference:  SH 90498 28742 (Leica 530)

Bwlch Height:  495.1m (converted to OSGM15, Leica 530)

Bwlch Grid Reference:  SH 90897 28658 (hand-held GPS via DoBIH)

Drop:  3o.9m (Leica 530)


Myrddyn Phillips (June 2020)






Mapping Mountains - Hill Reclassifications - The 500-Metre Tops of England and Wales - Deweys

St Raven’s Edge (NY 406 083) – Dewey addition (23rd reclassification)


This is one in a series of retrospective Hill Reclassification posts that detail hills whose status has altered in the listing of the Deweys and where I have had direct association with the status change.  These posts will tie in with a forthcoming Change Register giving detail to this list and its alterations since publication in the Mountain tables book.

The 500-Metre Tops of England and Wales are affectionately known after their hill list compiler; Michael Dewey.  This list mixes metric and imperial height in its criteria to bookend up to the 2000ft height band and takes in all hills in England, Isle of Man and Wales that are 500m and above and below 2000ft (609.6m) in height that have 30m minimum drop.

This list formed one of a number of lists that appeared in the Mountain tables book published by Constable in 1995 and at the time of publication comprised 373 hills with 164 in England, 5 in the Isle of Man and 204 in Wales.  The Deweys have undergone extensive revision since first publication with the initial stages forming the basis of this revision given below:


1995    Mountain tables published by Constable with 373 hills listed as Deweys.

April 2000    Strider (LDWA quarterly booklet) publishes contact details for David Purchase and Myrddyn Phillips who have found and list 24 and 14 possible new 500m tops respectively.

It was expanded versions of the above two lists that formed the basis of the next publication:

25th May 2000    List of Possible 500 Metre Tops by Michael Dewey listing 44 hills.

David Purchase expands his Additional Dewey 500m Hills and Myrddyn Phillips produces lists of English 500m hills to measure and Welsh 500m hills to measure.

These lists formed the basis of the next publication:

29th June 2000    Possible/Probable 500’s by Michael Dewey listing 77 hills.  Michael adopts following protocol; if one person proposes that a top should qualify as a 500 by personal survey, and is then confirmed by a second person, it should then be promoted to the main list.

April 2002    The 500+ Tops of England and Wales – The ‘New Deweys’ published in the Strider booklet and listing 66 new qualifying hills.

25th May 2006    Rob Woodall republishes Michael’s main and possible/probable lists on the RHB Yahoo group file database. 

Mountain tables by Michael Dewey

The details for this addition appear below:

The name the hill is listed by in the Deweys is St Raven’s Edge, and it is adjoined to the High Street group of hills which are situated in the Lake District in England, and it is positioned with the A592 road to its west, and has the town of Ambleside towards the south-west.

This hill was not included in the original 1995 Constable publication, but with a 593m summit spot height and col contouring between 550m – 560m that appear on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map, this hill has a minimum of 30m of drop according to contemporary Ordnance Survey maps and therefore was an automatic entry to the listing of Deweys. 

Extract from the Ordnance Survey 1:25,000 Explorer map

The above was noted by Myrddyn Phillips who forwarded the detail to the list author; Michael Dewey and the hill was added to the list on the 29th June 2000.


The full details for the hill are:

Name:  St Raven’s Edge

OS 1:50,000 map:  90

OS 1:25,000 map:  7

Summit Height:  593m (spot height)

Summit Grid Reference:  NY 40613 08381 (hand-held GPS via DoBIH)

Col Height:  c 549m (interpolation)

Col Grid Reference:  NY 40703 08834 (interpolation)

Drop:  c 44m (spot height summit and interpolated col)


Myrddyn Phillips (June 2020)






Mapping Mountains - Hill Reclassifications - The 500-Metre Tops of England and Wales - Deweys

Foel y Geifr (SH 716 050) – Dewey addition (22nd reclassification)


This is one in a series of retrospective Hill Reclassification posts that detail hills whose status has altered in the listing of the Deweys and where I have had direct association with the status change.  These posts will tie in with a forthcoming Change Register giving detail to this list and its alterations since publication in the Mountain tables book.

Foel y Geifr (SH 716 050) on left with Tarren y Gesail on the right

The 500-Metre Tops of England and Wales are affectionately known after their hill list compiler; Michael Dewey.  This list mixes metric and imperial height in its criteria to bookend up to the 2000ft height band and takes in all hills in England, Isle of Man and Wales that are 500m and above and below 2000ft (609.6m) in height that have 30m minimum drop.

This list formed one of a number of lists that appeared in the Mountain tables book published by Constable in 1995 and at the time of publication comprised 373 hills with 164 in England, 5 in the Isle of Man and 204 in Wales.  The Deweys have undergone extensive revision since first publication with the initial stages forming the basis of this revision given below:


1995    Mountain tables published by Constable with 373 hills listed as Deweys.

April 2000    Strider (LDWA quarterly booklet) publishes contact details for David Purchase and Myrddyn Phillips who have found and list 24 and 14 possible new 500m tops respectively.

It was expanded versions of the above two lists that formed the basis of the next publication:

25th May 2000    List of Possible 500 Metre Tops by Michael Dewey listing 44 hills.

David Purchase expands his Additional Dewey 500m Hills and Myrddyn Phillips produces lists of English 500m hills to measure and Welsh 500m hills to measure.

These lists formed the basis of the next publication:

29th June 2000    Possible/Probable 500’s by Michael Dewey listing 77 hills.  Michael adopts following protocol; if one person proposes that a top should qualify as a 500 by personal survey, and is then confirmed by a second person, it should then be promoted to the main list.

April 2002    The 500+ Tops of England and Wales – The ‘New Deweys’ published in the Strider booklet and listing 66 new qualifying hills.

25th May 2006    Rob Woodall republishes Michael’s main and possible/probable lists on the RHB Yahoo group file database. 


Mountain tables by Michael Dewey

The details for this addition appear below:

The name the hill is listed by in the Deweys is Foel y Geifr, and it is adjoined to the Cadair Idris group of hills which are situated in the south-western part of North Wales, and it is positioned with the B4405 road to its north-west, the A493 road to its south and the A487 road to its east, and has the town of Machynlleth towards the south-east.

This hill was not included in the original 1995 Constable publication, but with a 515m summit spot height and bwlch contouring between 480m – 490m that appear on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map, the interpolated drop value was estimated sufficient for this hill to be a potential new Dewey.

Extract from the Ordnance Survey 1:25,000 Explorer map

The above detail was noted by Myrddyn Phillips who then conducted a basic levelling survey of this hill on the 26th June 2000, resulting in 104½ft / 31.9m of drop.  These details were forwarded to the list author; Michael Dewey and the hill was added to the list with the date of survey given in the Remarks column accompanying the list.


The full details for the hill are:

Name:  Foel y Geifr

OS 1:50,000 map:  124

OS 1:25,000 map:  23

Summit Height:  515m (spot height)

Summit Grid Reference:  SH 71636 05099 (hand-held GPS via DoBIH)

Bwlch Height:  483m (relative to spot heighted summit and basic levelling survey drop)

Bwlch Grid Reference:  SH 71733 05408 (interpolation)

Drop:  32m (spot height summit and basic levelling survey drop)


Myrddyn Phillips (June 2020)






Mapping Mountains - Hill Reclassifications - The 500-Metre Tops of England and Wales - Deweys

Foel Ystrodur Fawr (SH 814 340) – Dewey addition (21st reclassification)


This is one in a series of retrospective Hill Reclassification posts that detail hills whose status has altered in the listing of the Deweys and where I have had direct association with the status change.  These posts will tie in with a forthcoming Change Register giving detail to this list and its alterations since publication in the Mountain tables book.

The 500-Metre Tops of England and Wales are affectionately known after their hill list compiler; Michael Dewey.  This list mixes metric and imperial height in its criteria to bookend up to the 2000ft height band and takes in all hills in England, Isle of Man and Wales that are 500m and above and below 2000ft (609.6m) in height that have 30m minimum drop.

This list formed one of a number of lists that appeared in the Mountain tables book published by Constable in 1995 and at the time of publication comprised 373 hills with 164 in England, 5 in the Isle of Man and 204 in Wales.  The Deweys have undergone extensive revision since first publication with the initial stages forming the basis of this revision given below:


1995    Mountain tables published by Constable with 373 hills listed as Deweys.

April 2000    Strider (LDWA quarterly booklet) publishes contact details for David Purchase and Myrddyn Phillips who have found and list 24 and 14 possible new 500m tops respectively.

It was expanded versions of the above two lists that formed the basis of the next publication:

25th May 2000    List of Possible 500 Metre Tops by Michael Dewey listing 44 hills.

David Purchase expands his Additional Dewey 500m Hills and Myrddyn Phillips produces lists of English 500m hills to measure and Welsh 500m hills to measure.

These lists formed the basis of the next publication:

29th June 2000    Possible/Probable 500’s by Michael Dewey listing 77 hills.  Michael adopts following protocol; if one person proposes that a top should qualify as a 500 by personal survey, and is then confirmed by a second person, it should then be promoted to the main list.

April 2002    The 500+ Tops of England and Wales – The ‘New Deweys’ published in the Strider booklet and listing 66 new qualifying hills.

25th May 2006    Rob Woodall republishes Michael’s main and possible/probable lists on the RHB Yahoo group file database. 


Mountain tables by Michael Dewey

The details for this addition appear below:

The name the hill is listed by in the Deweys is Foel Ystrodur Fawrand it is adjoined to the Arenig group of hills which are situated in the central part of North Wales, and it is positioned with the A4212 road to its north, the A470 road to its west and the A494 road to its south-east, and has the town of Y Bala towards the east.

This hill was not included in the original 1995 Constable publication, but with a 518m summit spot height and bwlch contouring between 480m – 490m that appear on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map, the interpolated drop value was estimated sufficient for this hill to be a potential new Dewey.

Extract from the Ordnance Survey 1:25,000 Explorer map

The above detail was noted by Myrddyn Phillips who then conducted a basic levelling survey of this hill on the 4th May 2000, resulting in 107ft / 32.6m of drop.  These details were forwarded to the list author; Michael Dewey and the hill was added to the list on the 25th May 2000.


The full details for the hill are:

Name:  Foel Ystrodur Fawr

OS 1:50,000 map:  124, 125

OS 1:25,000 map:  18, 23

Summit Height:  518m (spot height)

Summit Grid Reference:  SH 81446 34040 (hand-held GPS via DoBIH)

Bwlch Height:  485m (relative to spot heighted summit and basic levelling survey drop)

Bwlch Grid Reference:  SH 81361 34243 (interpolation)

Drop:  33m (spot height summit and basic levelling survey drop)


Myrddyn Phillips (June 2020)






Mapping Mountains - Hill Reclassifications - The 500-Metre Tops of England and Wales - Deweys

Y Blaen Llym (SH 685 464) – Dewey addition (20th reclassification)


This is one in a series of retrospective Hill Reclassification posts that detail hills whose status has altered in the listing of the Deweys and where I have had direct association with the status change.  These posts will tie in with a forthcoming Change Register giving detail to this list and its alterations since publication in the Mountain tables book.

The ridge from Y Blaen Llym leading to Allt Fawr

The 500-Metre Tops of England and Wales are affectionately known after their hill list compiler; Michael Dewey.  This list mixes metric and imperial height in its criteria to bookend up to the 2000ft height band and takes in all hills in England, Isle of Man and Wales that are 500m and above and below 2000ft (609.6m) in height that have 30m minimum drop.

This list formed one of a number of lists that appeared in the Mountain tables book published by Constable in 1995 and at the time of publication comprised 373 hills with 164 in England, 5 in the Isle of Man and 204 in Wales.  The Deweys have undergone extensive revision since first publication with the initial stages forming the basis of this revision given below:


1995    Mountain tables published by Constable with 373 hills listed as Deweys.

April 2000    Strider (LDWA quarterly booklet) publishes contact details for David Purchase and Myrddyn Phillips who have found and list 24 and 14 possible new 500m tops respectively.

It was expanded versions of the above two lists that formed the basis of the next publication:

25th May 2000    List of Possible 500 Metre Tops by Michael Dewey listing 44 hills.

David Purchase expands his Additional Dewey 500m Hills and Myrddyn Phillips produces lists of English 500m hills to measure and Welsh 500m hills to measure.

These lists formed the basis of the next publication:

29th June 2000    Possible/Probable 500’s by Michael Dewey listing 77 hills.  Michael adopts following protocol; if one person proposes that a top should qualify as a 500 by personal survey, and is then confirmed by a second person, it should then be promoted to the main list.

April 2002    The 500+ Tops of England and Wales – The ‘New Deweys’ published in the Strider booklet and listing 66 new qualifying hills.

25th May 2006    Rob Woodall republishes Michael’s main and possible/probable lists on the RHB Yahoo group file database. 


Mountain tables by Michael Dewey

The details for this addition appear below:

The name the hill is listed by in the Deweys is Y Blaen Llym, and it is adjoined to the Moelwynion group of hills which are situated in the north-western part of north Wales, and it is positioned with the A498 road to its north-west, the A4085 road to its west south-west, the A496 road to its south and the A470 road to its east, and has the town of Blaenau Ffestiniog towards the east south-east.

The Name: Y Blaen Llym is a partly invented and transposed name based on the proximity of Carreg Flaenllym, which is a prominent crag with its name appearing to the east of this hill’s summit on contemporary Ordnance Survey 1:25,000 Explorer maps.  The name was suggested as being appropriate for this hill by Paddy Buckley after an enquiry from Rob Woodall, with Paddy giving the translation of the crag as ‘rock of the sharp prow’ and the hill as ‘the sharp prow’.

This hill was not included in the original 1995 Constable publication, but with a 554m summit spot height and bwlch contouring between 520m – 530m that appear on the Ordnance Survey 1:25,000 Explorer map, the interpolated drop value was estimated sufficient for this hill to be a potential new Dewey.

Extract from the Ordnance Survey 1:25,000 Explorer map

The above detail was noted by Myrddyn Phillips who then conducted a basic levelling survey of this hill on the 5th May 2000, resulting in 100ft / 30.5m of drop.  These details were forwarded to the list author; Michael Dewey and the hill was added to the list on the 25th May 2000.

Since the inclusion of this hill in the Dewey list the Ordnance Survey Vector Map Local hosted on the Geograph website and which is entitled the Interactive Coverage Map became available online.  This mapping had many spot heights not on other publicly available Ordnance Survey maps and gives a 526m spot height on the area of this hill’s bwlch, and when coupled with the 554m summit spot height these values give this hill 28m of drop according to contemporary Ordnance Survey maps.

As the result from the basic levelling survey was near the minimum 30m qualifying drop value this hill was prioritised for a line survey which was conducted by John Barnard and Myrddyn Phillips on the 16th March 2010, resulting in 30.6m of drop which confirmed this hill’s Dewey status.


The full details for the hill are:

Name:  Y Blaen Llym

OS 1:50,000 map:  115

OS 1:25,000 map:  17

Summit Height:  554m (spot height)

Summit Grid Reference:  SH 68530 46413 (hand-held GPS via DoBIH)

Bwlch Height:  523m (relative to spot heighted summit and line surveyed drop)

Bwlch Grid Reference:  SH 68343 46613 (hand-held GPS via DoBIH)

Drop:  30.6m (level and staff line survey)


Myrddyn Phillips (June 2020)






Mapping Mountains - Hill Reclassifications - The 500-Metre Tops of England and Wales - Deweys

Pen Ochr y Bwlch (SH 809 172) – Dewey addition (19th reclassification)


This is one in a series of retrospective Hill Reclassification posts that detail hills whose status has altered in the listing of the Deweys and where I have had direct association with the status change.  These posts will tie in with a forthcoming Change Register giving detail to this list and its alterations since publication in the Mountain tables book.

The hill listed as Pen Ochr y Bwlch in the Deweys (SH 809 172)

The 500-Metre Tops of England and Wales are affectionately known after their hill list compiler; Michael Dewey.  This list mixes metric and imperial height in its criteria to bookend up to the 2000ft height band and takes in all hills in England, Isle of Man and Wales that are 500m and above and below 2000ft (609.6m) in height that have 30m minimum drop.

This list formed one of a number of lists that appeared in the Mountain tables book published by Constable in 1995 and at the time of publication comprised 373 hills with 164 in England, 5 in the Isle of Man and 204 in Wales.  The Deweys have undergone extensive revision since first publication with the initial stages forming the basis of this revision given below:


1995    Mountain tables published by Constable with 373 hills listed as Deweys.

April 2000    Strider (LDWA quarterly booklet) publishes contact details for David Purchase and Myrddyn Phillips who have found and list 24 and 14 possible new 500m tops respectively.

It was expanded versions of the above two lists that formed the basis of the next publication:

25th May 2000    List of Possible 500 Metre Tops by Michael Dewey listing 44 hills.

David Purchase expands his Additional Dewey 500m Hills and Myrddyn Phillips produces lists of English 500m hills to measure and Welsh 500m hills to measure.

These lists formed the basis of the next publication:

29th June 2000    Possible/Probable 500’s by Michael Dewey listing 77 hills.  Michael adopts following protocol; if one person proposes that a top should qualify as a 500 by personal survey, and is then confirmed by a second person, it should then be promoted to the main list.

April 2002    The 500+ Tops of England and Wales – The ‘New Deweys’ published in the Strider booklet and listing 66 new qualifying hills.

25th May 2006    Rob Woodall republishes Michael’s main and possible/probable lists on the RHB Yahoo group file database. 

Mountain tables by Michael Dewey


The details for this addition appear below:

The name the hill is listed by in the Deweys is Pen Ochr y Bwlch, and it is adjoined to the Aran group of hills which are situated in the central part of North Wales, and it is positioned with the A494 road to the north and the A470 road to the south, and has the town of Dolgellau towards the west.

The Name: Pen Ochr y Bwlch is a partly invented and transposed name based on the proximity of Ochr y Bwlch which is a prominent name that appears on contemporary Ordnance Survey maps.  Ochr y Bwlch strictly applies to the steep slope immediately above Bwlch Oerddrws which is to the south south-west of this hill’s summit, and does not necessary apply to either the hill name or its summit.

This hill was not included in the original 1995 Constable publication, but with a 564m summit spot height and bwlch contouring between 530m – 540m that appear on the Ordnance Survey 1:25,000 Explorer map, the interpolated drop value was estimated sufficient for this hill to be a potential new Dewey.

Extract from the Ordnance Survey 1:25,000 Explorer map

The above detail was noted by Myrddyn Phillips who then conducted a basic levelling survey of this hill on the 28th April 2000, resulting in 115ft / 35.1m of drop.  These details were forwarded to the list author; Michael Dewey and the hill was added to the list on the 25th May 2000.

Since the inclusion of this hill in the Dewey list the Ordnance Survey Vector Map Local hosted on the Geograph website and which is entitled the Interactive Coverage Map became available online.  This mapping had many spot heights not on other publicly available Ordnance Survey maps and gives a 533m spot height on the area of this hill’s bwlch, and when coupled with the 564m summit spot height these values give this hill 31m of drop according to contemporary Ordnance Survey maps.

The Trimble GeoXH 6000 gathering data at the summit of the hill named Pen Ochr y Bwlch in the Deweys

The Trimble GeoXH 6000 gathering data at the bwlch of the hill named Pen Ochr y Bwlch in the Deweys

This hill was subsequently surveyed by GNSS receiver by Myrddyn Phillips using a Trimble GeoXH 6000 on the 8th March 2014, resulting in a 564.3m summit height and a 530.5m bwlch height, with these values giving this hill 33.8m of drop and confirming its Dewey status.


The full details for the hill are:

Name:  Pen Ochr y Bwlch

OS 1:50,000 map:  124, 125

OS 1:25,000 map:  23

Summit Height:  564.3m (Trimble GeoXH 6000)

Summit Grid Reference:  SH 80957 17269 (Trimble GeoXH 6000)

Bwlch Height:  530.5m (Trimble GeoXH 6000)

Bwlch Grid Reference:  SH 81133 17386 (Trimble GeoXH 6000)

Drop:  33.8m (Trimble GeoXH 6000 summit and bwlch)


Myrddyn Phillips (June 2020)






Mapping Mountains - Hill Reclassifications - The 500-Metre Tops of England and Wales - Deweys

Carn Hyddgen (SN 792 908) – Dewey addition (18th reclassification)


This is one in a series of retrospective Hill Reclassification posts that detail hills whose status has altered in the listing of the Deweys and where I have had direct association with the status change.  These posts will tie in with a forthcoming Change Register giving detail to this list and its alterations since publication in the Mountain tables book.

The 500-Metre Tops of England and Wales are affectionately known after their hill list compiler; Michael Dewey.  This list mixes metric and imperial height in its criteria to bookend up to the 2000ft height band and takes in all hills in England, Isle of Man and Wales that are 500m and above and below 2000ft (609.6m) in height that have 30m minimum drop.

This list formed one of a number of lists that appeared in the Mountain tables book published by Constable in 1995 and at the time of publication comprised 373 hills with 164 in England, 5 in the Isle of Man and 204 in Wales.  The Deweys have undergone extensive revision since first publication with the initial stages forming the basis of this revision given below:


1995    Mountain tables published by Constable with 373 hills listed as Deweys.

April 2000    Strider (LDWA quarterly booklet) publishes contact details for David Purchase and Myrddyn Phillips who have found and list 24 and 14 possible new 500m tops respectively.

It was expanded versions of the above two lists that formed the basis of the next publication:

25th May 2000    List of Possible 500 Metre Tops by Michael Dewey listing 44 hills.

David Purchase expands his Additional Dewey 500m Hills and Myrddyn Phillips produces lists of English 500m hills to measure and Welsh 500m hills to measure.

These lists formed the basis of the next publication:

29th June 2000    Possible/Probable 500’s by Michael Dewey listing 77 hills.  Michael adopts following protocol; if one person proposes that a top should qualify as a 500 by personal survey, and is then confirmed by a second person, it should then be promoted to the main list.

April 2002    The 500+ Tops of England and Wales – The ‘New Deweys’ published in the Strider booklet and listing 66 new qualifying hills.

25th May 2006    Rob Woodall republishes Michael’s main and possible/probable lists on the RHB Yahoo group file database. 


Mountain tables by Michael Dewey

The details for this addition appear below:

The name the hill is listed by in the Deweys is Carn Hyddgen, and it is adjoined to the Pumlumon group of hills which are situated in the western part of Mid Wales, and it is positioned with the A487 road to the west, the A44 road to the south and the B4518 road to the east, and has the town of Machynlleth towards the north-north-west.

This hill was not included in the original 1995 Constable publication, but with a 566m summit spot height and bwlch contouring between 510m – 520m that appear on the Ordnance Survey 1:25,000 Explorer map, this hill was an automatic entry to the listing of Deweys.  However, its proximity to the hill named Foel Uchaf (SN 802 912) on contemporary Ordnance Survey maps, which is given a 565m summit spot height may have implicated it being missed from the original listing, and when Carn Hyddgen was included this may have led to the subsequent deletion of Foel Uchaf; the lower map heighted hill, which was later reinstated.

Extract from the Ordnance Survey 1:25,000 Explorer map

The above detail was noted by David Purchase and Myrddyn Phillips who worked independently but also exchanged all data.  These details were forwarded to the list author; Michael Dewey and the hill was added to the list on the 11th May 2000.

Extract from the Magic Maps website

Since the inclusion of this hill in the Dewey list the Ordnance Survey Vector Map Local hosted on the Geograph website and which is entitled the Interactive Coverage Map became available online.  This mapping had many spot heights not on other publicly available Ordnance Survey maps and gives a 514m spot height on the area of this hill’s bwlch, and when coupled with the 566m summit spot height these values give this hill 52m of drop.  The 514m spot height is also shown on Ordnance Survey data that appears on the Magic Maps website.


The full details for the hill are:

Name:  Carn Hyddgen

OS 1:50,000 map:  135

OS 1:25,000 map:  215

Summit Height:  566m (spot height)

Summit Grid Reference:  SN 79233 90831 (hand-held GPS via DoBIH)

Bwlch Height:  514m (spot height)

Bwlch Grid Reference:  SN 80386 92697 (spot height)

Drop:  52m (spot height summit and bwlch)


Myrddyn Phillips (May 2020)







Mapping Mountains - Hill Reclassifications - The 500-Metre Tops of England and Wales - Deweys

Stanky Hill (SO 163 764) – Dewey addition (17th reclassification)


This is one in a series of retrospective Hill Reclassification posts that detail hills whose status has altered in the listing of the Deweys and where I have had direct association with the status change.  These posts will tie in with a forthcoming Change Register giving detail to this list and its alterations since publication in the Mountain tables book.

The bwlch of Stanky Hill

The 500-Metre Tops of England and Wales are affectionately known after their hill list compiler; Michael Dewey.  This list mixes metric and imperial height in its criteria to bookend up to the 2000ft height band and takes in all hills in England, Isle of Man and Wales that are 500m and above and below 2000ft (609.6m) in height that have 30m minimum drop.

This list formed one of a number of lists that appeared in the Mountain tables book published by Constable in 1995 and at the time of publication comprised 373 hills with 164 in England, 5 in the Isle of Man and 204 in Wales.  The Deweys have undergone extensive revision since first publication with the initial stages forming the basis of this revision given below:


1995    Mountain tables published by Constable with 373 hills listed as Deweys.

April 2000    Strider (LDWA quarterly booklet) publishes contact details for David Purchase and Myrddyn Phillips who have found and list 24 and 14 possible new 500m tops respectively.

It was expanded versions of the above two lists that formed the basis of the next publication:

25th May 2000    List of Possible 500 Metre Tops by Michael Dewey listing 44 hills.

David Purchase expands his Additional Dewey 500m Hills and Myrddyn Phillips produces lists of English 500m hills to measure and Welsh 500m hills to measure.

These lists formed the basis of the next publication:

29th June 2000    Possible/Probable 500’s by Michael Dewey listing 77 hills.  Michael adopts following protocol; if one person proposes that a top should qualify as a 500 by personal survey, and is then confirmed by a second person, it should then be promoted to the main list.

April 2002    The 500+ Tops of England and Wales – The ‘New Deweys’ published in the Strider booklet and listing 66 new qualifying hills.

25th May 2006    Rob Woodall republishes Michael’s main and possible/probable lists on the RHB Yahoo group file database. 


Mountain tables by Michael Dewey

The details for this addition appear below:

The name the hill is listed by in the Deweys is Stanky Hill, and it is adjoined to the Radnor Forest group of hills which are situated in the north-eastern part of Mid Wales, and it is positioned with the B4355 road to its north, the A483 road to its west and the B4356 road to its south, and has the village of Bugeildy (Beguildy) towards the north-east.

This hill was not included in the original 1995 Constable publication, but with a 506m summit spot height and bwlch contouring between 470m – 480m that appear on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map, the interpolated drop value was estimated sufficient for this hill to be considered for Dewey status.  However, as the Ordnance Survey 1:50,000 Landranger map also shows a 407m spot height on the area of this hill’s bwlch this hill had not been considered for automatic entry to this list.

Extract from the Ordnance Survey 1:25,000 Explorer map

Extract from the Ordnance Survey 1:50,000 Landranger map

The above detail was noted by David Purchase and Myrddyn Phillips who worked independently but also exchanged all data.  On the 30th April 2000 Myrddyn Phillips conducted a basic levelling survey (BLS) of this hill, resulting in 103ft / 31.4m of drop.  These details were forwarded to the list author; Michael Dewey and the hill was added to the list on the 8th May 2000.

As the margin of uncertainty for the BLS method of surveying over terrain such as that on Stanky Hill is approximately +/- 1.5m and as the resulting 31.4m of drop was near the minimum 30m qualifying drop value, this hill was prioritised for a GNSS and level and staff line survey, and this took place on the 16th February 2012.  The summit and bwlch of this hill were surveyed by John Barnard, Graham Jackson and Myrddyn Phillips with assistance from Aled Williams, using a Leica 530 with 60 minutes of data gathered at each point.  During data collection the hill was also line surveyed from bwlch to summit and back to its bwlch, resulting in the drop value for this hill being ascertained from a further two different forms of surveying.

At the bwlch of Stanky Hill

The survey resulted in a 506.7m summit height and a 476.4m bwlch height, with these values giving this hill 30.3m of drop, which also matched that ascertained from the level and staff line survey, and confirmed this hill’s Dewey status. 


The full details for the hill are:

Name:  Stanky Hill

OS 1:50,000 map:  136, 148

OS 1:25,000 map:  214

Summit Height:  506.7m (Leica 530)

Summit Grid Reference:  SO 16390 76419 (Leica 530)

Bwlch Height:  476.4m (Leica 530)

Bwlch Grid Reference:  SO 16861 76416 (hand-held GPS during survey)

Drop:  30.3m (Leica 530 and level and staff line survey)


Myrddyn Phillips (May 2020)







Mapping Mountains - Hill Reclassifications - The 500-Metre Tops of England and Wales - Deweys

Carreg Cadno (SN 874 161) – Dewey addition (16th reclassification)


This is one in a series of retrospective Hill Reclassification posts that detail hills whose status has altered in the listing of the Deweys and where I have had direct association with the status change.  These posts will tie in with a forthcoming Change Register giving detail to this list and its alterations since publication in the Mountain tables book.

Carreg Cadno (SN 874 161)

The 500-Metre Tops of England and Wales are affectionately known after their hill list compiler; Michael Dewey.  This list mixes metric and imperial height in its criteria to bookend up to the 2000ft height band and takes in all hills in England, Isle of Man and Wales that are 500m and above and below 2000ft (609.6m) in height that have 30m minimum drop.

This list formed one of a number of lists that appeared in the Mountain tables book published by Constable in 1995 and at the time of publication comprised 373 hills with 164 in England, 5 in the Isle of Man and 204 in Wales.  The Deweys have undergone extensive revision since first publication with the initial stages forming the basis of this revision given below:


1995    Mountain tables published by Constable with 373 hills listed as Deweys.

April 2000    Strider (LDWA quarterly booklet) publishes contact details for David Purchase and Myrddyn Phillips who have found and list 24 and 14 possible new 500m tops respectively.

It was expanded versions of the above two lists that formed the basis of the next publication:

25th May 2000    List of Possible 500 Metre Tops by Michael Dewey listing 44 hills.

David Purchase expands his Additional Dewey 500m Hills and Myrddyn Phillips produces lists of English 500m hills to measure and Welsh 500m hills to measure.

These lists formed the basis of the next publication:

29th June 2000    Possible/Probable 500’s by Michael Dewey listing 77 hills.  Michael adopts following protocol; if one person proposes that a top should qualify as a 500 by personal survey, and is then confirmed by a second person, it should then be promoted to the main list.

April 2002    The 500+ Tops of England and Wales – The ‘New Deweys’ published in the Strider booklet and listing 66 new qualifying hills.

25th May 2006    Rob Woodall republishes Michael’s main and possible/probable lists on the RHB Yahoo group file database. 


Mountain tables by Michael Dewey

The details for this addition appear below:

The name the hill is listed by in the Deweys is Carreg Cadno, and it is adjoined to the Fforest Fawr group of hills which are situated in the western part of South Wales, and is positioned with the A4067 road to its west and the A4109 road to its south, and has the village of Abercraf (Abercrave) towards the south-west.

This hill was not included in the original 1995 Constable publication, but with a 538m summit spot height and bwlch contouring between 500m – 510m that appear on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map, the interpolated drop value was estimated sufficient for this hill to be a new Dewey.

Extract from the Ordnance Survey 1:25,000 Explorer map

The above was noted by Myrddyn Phillips and Rob Woodall, with Rob then conducting an on-site survey concentrating on the area of the bwlch, marking the approximate positions of the 510m contours and estimating the drop from the contour to the bwlch, resulting in an estimated 32m – 33m of drop.  These details were forwarded to the list author; Michael Dewey and the hill was added to the list on the 8th May 2000.

Since the inclusion of this hill in the Dewey list the Ordnance Survey Vector Map Local hosted on the Geograph website and which is entitled the Interactive Coverage Map became available online.  This mapping had many spot heights not on other publicly available Ordnance Survey maps and gives a 503m spot height on the area of this hill’s bwlch, and when coupled with the 538m summit spot height these values give this hill 35m of drop.  The 503m spot height is also shown on Ordnance Survey data that appears on the Magic Maps website.

Extract from the Magic Maps website

However, it was not until LIDAR became available that the details for this hill could be accurately re-assessed.  The LIDAR (Light Detection & Ranging) technique produced highly accurate height data that is now freely available for much of England and Wales.

The summit height and bwlch height and its position for this hill were subsequently ascertained from LIDAR analysis conducted by Aled Williams, resulting in a 537.9m summit height and a 502.8m bwlch height, with these values giving this hill 35.1m of drop, confirming its Dewey status. 

The Trimble GeoXH 6000 gathering data at the summit of Carreg Cadno

The Trimble GeoXH 6000 gathering data at the bwlch of Carreg Cadno

This hill was subsequently surveyed by GNSS receiver by Myrddyn Phillips and Aled Williams, with assistance from Mark Trengove on the 7th July 2019 using a Trimble GeoXH 6000, resulting in a 538.4m summit height and a 502.9m bwlch height, with these values giving this hill 35.5m of drop.


The full details for the hill are:

Name:  Carreg Cadno

OS 1:50,000 map:  160

OS 1:25,000 map:  12

Summit Height:  538.4m (Trimble GeoXH 6000)

Summit Grid Reference:  SN 87423 16132 (Trimble GeoXH 6000)

Bwlch Height:  502.9m (Trimble GeoXH 6000)

Bwlch Grid Reference:  SN 88466 17006 (Trimble GeoXH 6000)

Drop:  35.5m (Trimble GeoXH 6000 summit and bwlch)


Myrddyn Phillips (May 2020)







Mapping Mountains - Hill Reclassifications - The 500-Metre Tops of England and Wales - Deweys


THIS HILL HAS SUBSEQUENTLY BEEN DELETED FROM THE DEWEY LIST


Linghaw (SD 637 985) – Dewey addition (15th reclassification)


This is one in a series of retrospective Hill Reclassification posts that detail hills whose status has altered in the listing of the Deweys and where I have had direct association with the status change.  These posts will tie in with a forthcoming Change Register giving detail to this list and its alterations since publication in the Mountain tables book.

At the summit of Linghaw during the Leica 530 survey that subsequently deleted this hill from the list of Deweys

The 500-Metre Tops of England and Wales are affectionately known after their hill list compiler; Michael Dewey.  This list mixes metric and imperial height in its criteria to bookend up to the 2000ft height band and takes in all hills in England, Isle of Man and Wales that are 500m and above and below 2000ft (609.6m) in height that have 30m minimum drop.

This list formed one of a number of lists that appeared in the Mountain tables book published by Constable in 1995 and at the time of publication comprised 373 hills with 164 in England, 5 in the Isle of Man and 204 in Wales.  The Deweys have undergone extensive revision since first publication with the initial stages forming the basis of this revision given below:


1995    Mountain tables published by Constable with 373 hills listed as Deweys.

April 2000    Strider (LDWA quarterly booklet) publishes contact details for David Purchase and Myrddyn Phillips who have found and list 24 and 14 possible new 500m tops respectively.

It was expanded versions of the above two lists that formed the basis of the next publication:

25th May 2000    List of Possible 500 Metre Tops by Michael Dewey listing 44 hills.

David Purchase expands his Additional Dewey 500m Hills and Myrddyn Phillips produces lists of English 500m hills to measure and Welsh 500m hills to measure.

These lists formed the basis of the next publication:

29th June 2000    Possible/Probable 500’s by Michael Dewey listing 77 hills.  Michael adopts following protocol; if one person proposes that a top should qualify as a 500 by personal survey, and is then confirmed by a second person, it should then be promoted to the main list.

April 2002    The 500+ Tops of England and Wales – The ‘New Deweys’ published in the Strider booklet and listing 66 new qualifying hills.

25th May 2006    Rob Woodall republishes Michael’s main and possible/probable lists on the RHB Yahoo group file database. 

Mountain tables by Michael Dewey


The details for this addition appear below:

The name the hill is listed by in the Deweys is Linghaw, and it is adjoined to the Howgill Fells in the Great Shunner group of hills which are situated in the Yorkshire Dales in England, and it is positioned with the A685 road to its north, the M6 motorway to its west, and the A683 road to its east, and has the town of Sedbergh towards the south south-east.

This hill was not included in the original 1995 Constable publication, but with a small uppermost 500m ring contour and col contouring between 460m – 470m that appear on the Ordnance Survey 1:25,000 Explorer map, this hill has a minimum of 30m of drop according to contemporary Ordnance Survey maps and therefore was an automatic entry to the listing of Deweys. 

Extract from the Ordnance Survey 1:25,000 Explorer map

The above detail was noted by David Purchase and Myrddyn Phillips who worked independently but also exchanged all data.  These details were forwarded to the list author; Michael Dewey and the hill was added to the list on the 3rd May 2000.

As the summit height is the minimum required for qualification to Dewey status this hill was prioritised for a GNSS survey and this took place on the 20th October 2010.  The summit and col of this hill were surveyed by John Barnard, Graham Jackson and Myrddyn Phillips using a Leica 530 with 60 minutes of data gathered at the summit and 30 minutes at the col.  The survey resulted in a 498.9m summit height and a 463.45m col height, with these values giving this hill 35.4m of drop.  As the summit height is below 500m this hill was subsequently deleted from the list of Deweys (see later Hill Reclassifications post).

  
The full details for the hill are:

Name:  Linghaw

OS 1:50,000 map:  97

OS 1:25,000 map:  19

Summit Height:  c 500m (interpolation)

Summit Grid Reference:  SD 63764 98540 (interpolation)

Col Height:  c 465m (interpolation)

Col Grid Reference:  SD 63976 98485 (interpolation)

Drop:  c 35m (interpolation)


Myrddyn Phillips (May 2020)







Mapping Mountains - Hill Reclassifications - The 500-Metre Tops of England and Wales - Deweys

Moel Cae-howel (SH 978 330) – Dewey addition (14th reclassification)


This is one in a series of retrospective Hill Reclassification posts that detail hills whose status has altered in the listing of the Deweys and where I have had direct association with the status change.  These posts will tie in with a forthcoming Change Register giving detail to this list and its alterations since publication in the Mountain tables book.

Moel Cae-howel (SH 978 330)

The 500-Metre Tops of England and Wales are affectionately known after their hill list compiler; Michael Dewey.  This list mixes metric and imperial height in its criteria to bookend up to the 2000ft height band and takes in all hills in England, Isle of Man and Wales that are 500m and above and below 2000ft (609.6m) in height that have 30m minimum drop.

This list formed one of a number of lists that appeared in the Mountain tables book published by Constable in 1995 and at the time of publication comprised 373 hills with 164 in England, 5 in the Isle of Man and 204 in Wales.  The Deweys have undergone extensive revision since first publication with the initial stages forming the basis of this revision given below:


1995    Mountain tables published by Constable with 373 hills listed as Deweys.

April 2000    Strider (LDWA quarterly booklet) publishes contact details for David Purchase and Myrddyn Phillips who have found and list 24 and 14 possible new 500m tops respectively.

It was expanded versions of the above two lists that formed the basis of the next publication:

25th May 2000    List of Possible 500 Metre Tops by Michael Dewey listing 44 hills.

David Purchase expands his Additional Dewey 500m Hills and Myrddyn Phillips produces lists of English 500m hills to measure and Welsh 500m hills to measure.

These lists formed the basis of the next publication:

29th June 2000    Possible/Probable 500’s by Michael Dewey listing 77 hills.  Michael adopts following protocol; if one person proposes that a top should qualify as a 500 by personal survey, and is then confirmed by a second person, it should then be promoted to the main list.

April 2002    The 500+ Tops of England and Wales – The ‘New Deweys’ published in the Strider booklet and listing 66 new qualifying hills.

25th May 2006    Rob Woodall republishes Michael’s main and possible/probable lists on the RHB Yahoo group file database. 


Mountain tables by Michael Dewey

The details for this addition appear below:

The name the hill is listed by and its composition in the Deweys is Moel Cae-howel, and it is adjoined to the Y Berwyn group of hills which are situated in the south-eastern part of North Wales, and it is positioned with the B4391 road to its north and the B4403 road to its west, and has the town of Y Bala towards the north-west.

This hill was not included in the original 1995 Constable publication, but with a 508m summit spot height and bwlch contouring between 450m – 460m that appear on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map, this hill has a minimum of 30m of drop according to contemporary Ordnance Survey maps and therefore was an automatic entry to the listing of Deweys. 

Extract from the Ordnance Survey 1:25,000 Explorer map

The above was noted by Myrddyn Phillips and these details were forwarded to the list author; Michael Dewey and the hill was added to the list on the 3rd May 2000. 


The full details for the hill are:

Name:  Moel Cae-howel

OS 1:50,000 map:  125

OS 1:25,000 map:  18, 23

Summit Height:  508m (spot height)

Summit Grid Reference:  SH 97832 33087 (hand-held GPS via DoBIH)

Bwlch Height:  c 459m (interpolation)

Bwlch Grid Reference:  SH 98347 32559 (interpolation)

Drop:  c 49m (spot height summit and interpolated bwlch)


Myrddyn Phillips (May 2020)







Mapping Mountains - Hill Reclassifications - The 500-Metre Tops of England and Wales - Deweys

Foel Boeth (SH 804 478) – Dewey addition (13th reclassification)


This is one in a series of retrospective Hill Reclassification posts that detail hills whose status has altered in the listing of the Deweys and where I have had direct association with the status change.  These posts will tie in with a forthcoming Change Register giving detail to this list and its alterations since publication in the Mountain tables book.

The 500-Metre Tops of England and Wales are affectionately known after their hill list compiler; Michael Dewey.  This list mixes metric and imperial height in its criteria to bookend up to the 2000ft height band and takes in all hills in England, Isle of Man and Wales that are 500m and above and below 2000ft (609.6m) in height that have 30m minimum drop.

This list formed one of a number of lists that appeared in the Mountain tables book published by Constable in 1995 and at the time of publication comprised 373 hills with 164 in England, 5 in the Isle of Man and 204 in Wales.  The Deweys have undergone extensive revision since first publication with the initial stages forming the basis of this revision given below:


1995    Mountain tables published by Constable with 373 hills listed as Deweys.

April 2000    Strider (LDWA quarterly booklet) publishes contact details for David Purchase and Myrddyn Phillips who have found and list 24 and 14 possible new 500m tops respectively.

It was expanded versions of the above two lists that formed the basis of the next publication:

25th May 2000    List of Possible 500 Metre Tops by Michael Dewey listing 44 hills.

David Purchase expands his Additional Dewey 500m Hills and Myrddyn Phillips produces lists of English 500m hills to measure and Welsh 500m hills to measure.

These lists formed the basis of the next publication:

29th June 2000    Possible/Probable 500’s by Michael Dewey listing 77 hills.  Michael adopts following protocol; if one person proposes that a top should qualify as a 500 by personal survey, and is then confirmed by a second person, it should then be promoted to the main list.

April 2002    The 500+ Tops of England and Wales – The ‘New Deweys’ published in the Strider booklet and listing 66 new qualifying hills.

25th May 2006    Rob Woodall republishes Michael’s main and possible/probable lists on the RHB Yahoo group file database. 


Mountain tables by Michael Dewey

The details for this addition appear below:

The name the hill is listed by in the Deweys is Foel Boeth, and it is adjoined to the Arenig group of hills which are situated in the central part of North Wales, and it is positioned with the A5 road to its north-east, the B4406 road to its north north-west, the A470 road to its west and the B4407 road to its south-east, and has the village of Penmachno towards the north north-west.

Extract from the Ordnance Survey 1:25,000 Explorer map

This hill was not included in the original 1995 Constable publication, but with a 509m summit spot height and bwlch contouring between 430m – 440m that appear on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map, this hill has a minimum of 30m of drop according to contemporary Ordnance Survey maps and therefore was an automatic entry to the listing of Deweys. 

Extract from the Ordnance Survey 1:50,000 Landranger map

The above detail was noted by David Purchase and Myrddyn Phillips who worked independently but also exchanged all data.  These details were forwarded to the list author; Michael Dewey and the hill was added to the list on the 3rd May 2000.


The full details for the hill are:

Name:  Foel Boeth

OS 1:50,000 map:  116

OS 1:25,000 map:  18

Summit Height:  509m (spot height)

Summit Grid Reference:  SH 80481 47800 (hand-held GPS via DoBIH)

Bwlch Height:  c 439m (interpolation)

Bwlch Grid Reference:  SH 79415 46274 (interpolation)

Drop:  c 70m (spot height summit and interpolated bwlch)


Myrddyn Phillips (May 2020)







Mapping Mountains - Hill Reclassifications - The 500-Metre Tops of England and Wales - Deweys

Blaydike Moss (SD 852 772) – Dewey addition (12th reclassification)


This is one in a series of retrospective Hill Reclassification posts that detail hills whose status has altered in the listing of the Deweys and where I have had direct association with the status change.  These posts will tie in with a forthcoming Change Register giving detail to this list and its alterations since publication in the Mountain tables book.

LIDAR summit image of Blaydike Moss (SD 852 772)

The 500-Metre Tops of England and Wales are affectionately known after their hill list compiler; Michael Dewey.  This list mixes metric and imperial height in its criteria to bookend up to the 2000ft height band and takes in all hills in England, Isle of Man and Wales that are 500m and above and below 2000ft (609.6m) in height that have 30m minimum drop.

This list formed one of a number of lists that appeared in the Mountain tables book published by Constable in 1995 and at the time of publication comprised 373 hills with 164 in England, 5 in the Isle of Man and 204 in Wales.  The Deweys have undergone extensive revision since first publication with the initial stages forming the basis of this revision given below:


1995    Mountain tables published by Constable with 373 hills listed as Deweys.

April 2000    Strider (LDWA quarterly booklet) publishes contact details for David Purchase and Myrddyn Phillips who have found and list 24 and 14 possible new 500m tops respectively.

It was expanded versions of the above two lists that formed the basis of the next publication:

25th May 2000    List of Possible 500 Metre Tops by Michael Dewey listing 44 hills.

David Purchase expands his Additional Dewey 500m Hills and Myrddyn Phillips produces lists of English 500m hills to measure and Welsh 500m hills to measure.

These lists formed the basis of the next publication:

29th June 2000    Possible/Probable 500’s by Michael Dewey listing 77 hills.  Michael adopts following protocol; if one person proposes that a top should qualify as a 500 by personal survey, and is then confirmed by a second person, it should then be promoted to the main list.

April 2002    The 500+ Tops of England and Wales – The ‘New Deweys’ published in the Strider booklet and listing 66 new qualifying hills.

25th May 2006    Rob Woodall republishes Michael’s main and possible/probable lists on the RHB Yahoo group file database. 


Mountain tables by Michael Dewey

The details for this addition appear below:

The name the hill is listed by in the Deweys is Blaydike Moss, and it is adjoined to the Ingleborough group of hills which are situated in the Yorkshire Dales in England, and it is positioned with the B6479 road to its south-west and the B6160 road to its east, and has the village of Horton in Ribblesdale towards the south-west.

This hill was not included in the original 1995 Constable publication, but with a 510m summit spot height and col contouring between 470m – 480m that appear on the Ordnance Survey 1:25,000 Explorer map, this hill has a minimum of 30m of drop according to contemporary Ordnance Survey maps and therefore was an automatic entry to the listing of Deweys. 

Extract from the Ordnance Survey 1:25,000 Explorer map

The above was noted by Myrddyn Phillips and these details were forwarded to the list author; Michael Dewey, and the hill was added to the list on the 3rd May 2000.

Since the inclusion of this hill in the Dewey list the Ordnance Survey Vector Map Local hosted on the Geograph website and which is entitled the Interactive Coverage Map became available online.  This mapping had many spot heights not on other publicly available Ordnance Survey maps and gives a 477m spot height on the area of this hill’s col, and when coupled with the 510m summit spot height these values give this hill 33m of drop.  The 477m spot height is also shown on Ordnance Survey data that appears on the Magic Maps website.

Extract from the Magic Maps website

However, it was not until LIDAR became available that the details for this hill could be accurately re-assessed.  The LIDAR (Light Detection & Ranging) technique produced highly accurate height data that is now freely available for much of England and Wales.

LIDAR col image of Blaydike Moss

The summit and col heights for this hill were subsequently ascertained from LIDAR analysis conducted by Myrddyn Phillips, resulting in a 510.1m summit height and 476.6m col height, with these values giving this hill 33.5m of drop, confirming its Dewey status. 


The full details for the hill are:

Name:  Blaydike Moss

OS 1:50,000 map:  98

OS 1:25,000 map:  2, 30

Summit Height:  510.1m (LIDAR)

Summit Grid Reference:  SD 85261 77264 (LIDAR)

Col Height:  476.6m (LIDAR)

Col Grid Reference:  SD 84317 77373 (LIDAR)

Drop:  33.5m (LIDAR)


Myrddyn Phillips (May 2020)







Mapping Mountains - Hill Reclassifications - The 500-Metre Tops of England and Wales - Deweys

Moel y Llyn East Top (SN 717 912) – Dewey addition (11th reclassification)


This is one in a series of retrospective Hill Reclassification posts that detail hills whose status has altered in the listing of the Deweys and where I have had direct association with the status change.  These posts will tie in with a forthcoming Change Register giving detail to this list and its alterations since publication in the Mountain tables book.

The 500-Metre Tops of England and Wales are affectionately known after their hill list compiler; Michael Dewey.  This list mixes metric and imperial height in its criteria to bookend up to the 2000ft height band and takes in all hills in England, Isle of Man and Wales that are 500m and above and below 2000ft (609.6m) in height that have 30m minimum drop.

This list formed one of a number of lists that appeared in the Mountain tables book published by Constable in 1995 and at the time of publication comprised 373 hills with 164 in England, 5 in the Isle of Man and 204 in Wales.  The Deweys have undergone extensive revision since first publication with the initial stages forming the basis of this revision given below:


1995    Mountain tables published by Constable with 373 hills listed as Deweys.

April 2000    Strider (LDWA quarterly booklet) publishes contact details for David Purchase and Myrddyn Phillips who have found and list 24 and 14 possible new 500m tops respectively.

It was expanded versions of the above two lists that formed the basis of the next publication:

25th May 2000    List of Possible 500 Metre Tops by Michael Dewey listing 44 hills.

David Purchase expands his Additional Dewey 500m Hills and Myrddyn Phillips produces lists of English 500m hills to measure and Welsh 500m hills to measure.

These lists formed the basis of the next publication:

29th June 2000    Possible/Probable 500’s by Michael Dewey listing 77 hills.  Michael adopts following protocol; if one person proposes that a top should qualify as a 500 by personal survey, and is then confirmed by a second person, it should then be promoted to the main list.

April 2002    The 500+ Tops of England and Wales – The ‘New Deweys’ published in the Strider booklet and listing 66 new qualifying hills.

25th May 2006    Rob Woodall republishes Michael’s main and possible/probable lists on the RHB Yahoo group file database. 


Mountain tables by Michael Dewey

The details for this addition appear below:

The name the hill is listed by in the Deweys is Moel y Llyn East Top, and it is adjoined to the Pumlumon group of hills which are situated in the central part of Wales, and it is positioned with the A487 road to its west and a minor road to its south, and has the town of Machynlleth towards the north north-east.

The Name: Moel y Llyn East Top is an invented and directional name based on this hill’s proximity to the adjacent and higher hill of Moel y Llyn (SN 712 916), although topographically it is adjoined to Banc Bwlch y Garreg (SN 729 918).  This hill remains unnamed on historic and contemporary Ordnance Survey maps.

This hill was not included in the original 1995 Constable publication, but with a 510m uppermost summit contour and bwlch contouring between 470m – 480m that appear on the Ordnance Survey 1:25,000 Explorer map, this hill has a minimum of 30m of drop according to contemporary Ordnance Survey maps and therefore was an automatic entry to the listing of Deweys. 

Extract from the Ordnance Survey 1:25,000 Explorer map

The above was noted by Myrddyn Phillips and these details were forwarded to the list author; Michael Dewey and the hill was added to the list on the 3rd May 2000.

Extract from the WalkLakes website

The summit of this hill has subsequently been spot heighted as 511m on the WalkLakes website which hosts an interactive map originated from the Ordnance Survey Open Data programme.


The full details for the hill are:

Name:  Moel y Llyn East Top

OS 1:50,000 map:  135

OS 1:25,000 map:  23

Summit Height:  511m (spot height)

Summit Grid Reference:  SN 71753 91288 (hand-held GPS via DoBIH)

Bwlch Height:  c 478m (interpolation)

Bwlch Grid Reference:  SN 72333 91567 (interpolation)

Drop:  c 33m (spot height summit and interpolated bwlch)


Myrddyn Phillips (May 2020)







Mapping Mountains - Hill Reclassifications - The 500-Metre Tops of England and Wales - Deweys

Pen Dihewyd (SN 778 797) – Dewey addition (10th reclassification)


This is one in a series of retrospective Hill Reclassification posts that detail hills whose status has altered in the listing of the Deweys and where I have had direct association with the status change.  These posts will tie in with a forthcoming Change Register giving detail to this list and its alterations since publication in the Mountain tables book.

Pen Dihewyd (SN 778 797)

The 500-Metre Tops of England and Wales are affectionately known after their hill list compiler; Michael Dewey.  This list mixes metric and imperial height in its criteria to bookend up to the 2000ft height band and takes in all hills in England, Isle of Man and Wales that are 500m and above and below 2000ft (609.6m) in height that have 30m minimum drop.

This list formed one of a number of lists that appeared in the Mountain tables book published by Constable in 1995 and at the time of publication comprised 373 hills with 164 in England, 5 in the Isle of Man and 204 in Wales.  The Deweys have undergone extensive revision since first publication with the initial stages forming the basis of this revision given below:


1995    Mountain tables published by Constable with 373 hills listed as Deweys.

April 2000    Strider (LDWA quarterly booklet) publishes contact details for David Purchase and Myrddyn Phillips who have found and list 24 and 14 possible new 500m tops respectively.

It was expanded versions of the above two lists that formed the basis of the next publication:

25th May 2000    List of Possible 500 Metre Tops by Michael Dewey listing 44 hills.

David Purchase expands his Additional Dewey 500m Hills and Myrddyn Phillips produces lists of English 500m hills to measure and Welsh 500m hills to measure.

These lists formed the basis of the next publication:

29th June 2000    Possible/Probable 500’s by Michael Dewey listing 77 hills.  Michael adopts following protocol; if one person proposes that a top should qualify as a 500 by personal survey, and is then confirmed by a second person, it should then be promoted to the main list.

April 2002    The 500+ Tops of England and Wales – The ‘New Deweys’ published in the Strider booklet and listing 66 new qualifying hills.

25th May 2006    Rob Woodall republishes Michael’s main and possible/probable lists on the RHB Yahoo group file database. 


Mountain tables by Michael Deweys

The details for this addition appear below:

The name the hill is listed by in the Deweys is Pen Dihewyd, and it is adjoined to the Elenydd group of hills which are situated in the central part of Wales, and it is positioned with the A44 road to its north, the A4120 road to its west and the B4574 road to its south south-west, and has the village of Ponterwyd towards the west north-west.

This hill was not included in the original 1995 Constable publication, but with a 513m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and bwlch contouring between 470m – 480m that appears on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map, this hill has a minimum of 30m of drop according to contemporary Ordnance Survey maps and therefore was an automatic entry to the listing of Deweys. 

Extract from the Ordnance Survey 1:25,000 Explorer map

The above was noted by Myrddyn Phillips and these details were forwarded to the list author; Michael Dewey and the hill was added to the list on the 3rd May 2000.


The full details for the hill are:

Name:  Pen Dihewyd

OS 1:50,000 map:  135, 147

OS 1:25,000 map:  213

Summit Height:  513m (spot height)

Summit Grid Reference:  SN 77882 79702 (hand-help GPS via DoBIH)

Bwlch Height:  c 478m (interpolation)

Bwlch Grid Reference:  SN 77994 79730 (interpolation)

Drop:  c 35m (spot height summit and interpolated bwlch)


Myrddyn Phillips (May 2020)







Mapping Mountains - Hill Reclassifications - The 500-Metre Tops of England and Wales - Deweys

Craig Fawr (SN 879 638) – Dewey addition (9th reclassification)


This is one in a series of retrospective Hill Reclassification posts that detail hills whose status has altered in the listing of the Deweys and where I have had direct association with the status change.  These posts will tie in with a forthcoming Change Register giving detail to this list and its alterations since publication in the Mountain tables book.

The view from the summit of Craig Fawr

The 500-Metre Tops of England and Wales are affectionately known after their hill list compiler; Michael Dewey.  This list mixes metric and imperial height in its criteria to bookend up to the 2000ft height band and takes in all hills in England, Isle of Man and Wales that are 500m and above and below 2000ft (609.6m) in height that have 30m minimum drop.

This list formed one of a number of lists that appeared in the Mountain tables book published by Constable in 1995 and at the time of publication comprised 373 hills with 164 in England, 5 in the Isle of Man and 204 in Wales.  The Deweys have undergone extensive revision since first publication with the initial stages forming the basis of this revision given below:


1995    Mountain tables published by Constable with 373 hills listed as Deweys.

April 2000    Strider (LDWA quarterly booklet) publishes contact details for David Purchase and Myrddyn Phillips who have found and list 24 and 14 possible new 500m tops respectively.

It was expanded versions of the above two lists that formed the basis of the next publication:

25th May 2000    List of Possible 500 Metre Tops by Michael Dewey listing 44 hills.

David Purchase expands his Additional Dewey 500m Hills and Myrddyn Phillips produces lists of English 500m hills to measure and Welsh 500m hills to measure.

These lists formed the basis of the next publication:

29th June 2000    Possible/Probable 500’s by Michael Dewey listing 77 hills.  Michael adopts following protocol; if one person proposes that a top should qualify as a 500 by personal survey, and is then confirmed by a second person, it should then be promoted to the main list.

April 2002    The 500+ Tops of England and Wales – The ‘New Deweys’ published in the Strider booklet and listing 66 new qualifying hills.

25th May 2006    Rob Woodall republishes Michael’s main and possible/probable lists on the RHB Yahoo group file database. 


Mountain tables by Michael Dewey

The details for this addition appear below:

The name the hill is listed by in the Deweys is Craig Fawr, and it is adjoined to the Elenydd group of hills which are situated in the central part of Wales, and it is positioned with the A470 road to its east, and has the Claerwen Reservoir to its immediate west north-west, and the town of Rhaeadr Gwy (Rhayader) towards the east north-east.

This hill was not included in the original 1995 Constable publication, but with a 519m summit spot height that appears on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map and a 477m bwlch spot height that appears on the Ordnance Survey 1:25,000 Explorer map, this hill has a minimum of 42m of drop according to contemporary Ordnance Survey maps and therefore was an automatic entry to the listing of Deweys.   

Extract from the Ordnance Survey 1:25,000 Explorer map

The above detail was noted by David Purchase and Myrddyn Phillips who worked independently but also exchanged all data.  These details were forwarded to the list author; Michael Dewey and the hill was added to the list on the 3rd May 2000.

Gathering data with the Trimble GeoXH 6000 at the summit of Craig Fawr (SN 879 638)

This hill was subsequently surveyed by GNSS receiver by Myrddyn Phillips on the 27th February 2019 using a Trimble GeoXH 6000, resulting in a 517.9m summit height and a 475.7m bwlch height, with these values giving this hill 42.1m of drop confirming its Dewey status.


The full details for the hill are:

Name:  Craig Fawr

OS 1:50,000 map:  147

OS 1:25,000 map:  187, 200

Summit Height:  517.9m (Trimble GeoXH 6000)

Summit Grid Reference:  SN 87939 63846 (Trimble GeoXH 6000)

Bwlch Height:  475.7m (Trimble GeoXH 6000)

Bwlch Grid Reference:  SN 88241 64748 (Trimble GeoXH 6000)

Drop:  42.1m (Trimble GeoXH 6000)


Myrddyn Phillips (May 2020)







Mapping Mountains - Hill Reclassifications - The 500-Metre Tops of England and Wales - Deweys

Priddellau (SN 854 677) – Dewey addition (8th reclassification)


This is one in a series of retrospective Hill Reclassification posts that detail hills whose status has altered in the listing of the Deweys and where I have had direct association with the status change.  These posts will tie in with a forthcoming Change Register giving detail to this list and its alterations since publication in the Mountain tables book.

At the summit of Priddellau (SN 854 677)

The 500-Metre Tops of England and Wales are affectionately known after their hill list compiler; Michael Dewey.  This list mixes metric and imperial height in its criteria to bookend up to the 2000ft height band and takes in all hills in England, Isle of Man and Wales that are 500m and above and below 2000ft (609.6m) in height that have 30m minimum drop.

This list formed one of a number of lists that appeared in the Mountain tables book published by Constable in 1995 and at the time of publication comprised 373 hills with 164 in England, 5 in the Isle of Man and 204 in Wales.  The Deweys have undergone extensive revision since first publication with the initial stages forming the basis of this revision given below:


1995    Mountain tables published by Constable with 373 hills listed as Deweys.

April 2000    Strider (LDWA quarterly booklet) publishes contact details for David Purchase and Myrddyn Phillips who have found and list 24 and 14 possible new 500m tops respectively.

It was expanded versions of the above two lists that formed the basis of the next publication:

25th May 2000    List of Possible 500 Metre Tops by Michael Dewey listing 44 hills.

David Purchase expands his Additional Dewey 500m Hills and Myrddyn Phillips produces lists of English 500m hills to measure and Welsh 500m hills to measure.

These lists formed the basis of the next publication:

29th June 2000    Possible/Probable 500’s by Michael Dewey listing 77 hills.  Michael adopts following protocol; if one person proposes that a top should qualify as a 500 by personal survey, and is then confirmed by a second person, it should then be promoted to the main list.

April 2002    The 500+ Tops of England and Wales – The ‘New Deweys’ published in the Strider booklet and listing 66 new qualifying hills.

25th May 2006    Rob Woodall republishes Michael’s main and possible/probable lists on the RHB Yahoo group file database. 

Mountain tables by Michael Dewey

The details for this addition appear below:

The name the hill is listed by in the Deweys is Priddellau, and it is adjoined to the Elenydd group of hills which are situated in the central part of Wales, and it is positioned with the B4343 road to its west and the A470 road to its north-east, and has the Claerwen Reservoir to its south and the Penygarreg Reservoir to its east, and the town of Rhaeadr Gwy (Rhayader) towards the east.

This hill was not included in the original 1995 Constable publication, but with a 533m summit spot height and a 503m bwlch spot height that appear on the Ordnance Survey 1:25,000 Explorer map, this hill has a minimum of 30m of drop according to contemporary Ordnance Survey maps and therefore was an automatic entry to the listing of Deweys.    

Extract from the Ordnance Survey 1:25,000 Explorer map

The above detail was noted by David Purchase and Myrddyn Phillips who worked independently but also exchanged all data.  These details were forwarded to the list author; Michael Dewey and the hill was added to the list on the 3rd May 2000.

Extract from the WalkLakes website

As people became interested in the Deweys and visiting the listed hills, it was noted that there is higher ground toward the east north-east compared to the SN 85076 67642 position of the 533m spot height on the Ordnance Survey 1:25,000 Explorer map, with a better representation of the summit position being SN 85454 67796 with the ground at this position estimated as 1m higher.  This position has subsequently been spot heighted as 534m on the WalkLakes website which hosts an interactive map originated from the Ordnance Survey Open Data programme.


The full details for the hill are:

Name:  Priddellau

OS 1:50,000 map:  135, 136, 147

OS 1:25,000 map:  187, 200

Summit Height:  534m (spot height)

Summit Grid Reference:  SN 85454 67796 (hand-held GPS via DoBIH)

Bwlch Height:  503m (spot height)

Bwlch Grid Reference:  SN 85360 68251 (spot height)

Drop:  31m (spot height summit and bwlch)


Myrddyn Phillips (April 2020)






Mapping Mountains - Hill Reclassifications - The 500-Metre Tops of England and Wales - Deweys

THIS HILL HAS SUBSEQUENTLY BEEN DELETED FROM THE DEWEY LIST

Llechwedd Llwyd (SN 838 814) – Dewey addition (7th reclassification)

This is one in a series of retrospective Hill Reclassification posts that detail hills whose status has altered in the listing of the Deweys and where I have had direct association with the status change.  These posts will tie in with a forthcoming Change Register giving detail to this list and its alterations since publication in the Mountain tables book.

LIDAR image of Llechwedd Llwyd (SN 838 814)

The 500-Metre Tops of England and Wales are affectionately known after their hill list compiler; Michael Dewey.  This list mixes metric and imperial height in its criteria to bookend up to the 2000ft height band and takes in all hills in England, Isle of Man and Wales that are 500m and above and below 2000ft (609.6m) in height that have 30m minimum drop.

This list formed one of a number of lists that appeared in the Mountain tables book published by Constable in 1995 and at the time of publication comprised 373 hills with 164 in England, 5 in the Isle of Man and 204 in Wales.  The Deweys have undergone extensive revision since first publication with the initial stages forming the basis of this revision given below:


1995    Mountain tables published by Constable with 373 hills listed as Deweys.

April 2000    Strider (LDWA quarterly booklet) publishes contact details for David Purchase and Myrddyn Phillips who have found and list 24 and 14 possible new 500m tops respectively.

It was expanded versions of the above two lists that formed the basis of the next publication:

25th May 2000    List of Possible 500 Metre Tops by Michael Dewey listing 44 hills.

David Purchase expands his Additional Dewey 500m Hills and Myrddyn Phillips produces lists of English 500m hills to measure and Welsh 500m hills to measure.

These lists formed the basis of the next publication:

29th June 2000    Possible/Probable 500’s by Michael Dewey listing 77 hills.  Michael adopts following protocol; if one person proposes that a top should qualify as a 500 by personal survey, and is then confirmed by a second person, it should then be promoted to the main list.

April 2002    The 500+ Tops of England and Wales – The ‘New Deweys’ published in the Strider booklet and listing 66 new qualifying hills.

25th May 2006    Rob Woodall republishes Michael’s main and possible/probable lists on the RHB Yahoo group file database. 


Mountain tables by Michael Dewey

The details for this addition appear below:

The name the hill is listed by in the Deweys is Llechwedd Llwyd, and it is adjoined to the Elenydd group of hills which are situated in the north-western part of mid Wales, and it is positioned with the A44 road to its north, the A4120 road to its west south-west and the A470 road to its south-east, and has the village of Llangurig towards the east south-east.

This hill was not included in the original 1995 Constable publication, but with a 535m summit spot height and bwlch contouring between 500m – 510m that appear on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map, the interpolated drop value was estimated sufficient for this hill to be a potential new Dewey. 

Extract from the Ordnance Survey 1:25,000 Explorer map

The above was noted by Myrddyn Phillips and these details were forwarded to the list author; Michael Dewey and the hill was added to the list on the 3rd May 2000. 


The full details for the hill are:

Name:  Llechwedd Llwyd

OS 1:50,000 map:  135, 136

OS 1:25,000 map:  214

Summit Height:  535m (spot height)

Summit Grid Reference:  SN 83868 81410 (hand-held GPS via DoBIH)

Bwlch Height:  c 505m (interpolation)

Bwlch Grid Reference:  SN 84160 80506 (interpolation)

Drop:  c 30m (spot height summit and interpolated bwlch)


Myrddyn Phillips (April 2020)







Mapping Mountains - Hill Reclassifications - The 500-Metre Tops of England and Wales - Deweys

Bryn-llus (SJ 085 408) – Dewey addition (6th reclassification)


This is one in a series of retrospective Hill Reclassification posts that detail hills whose status has altered in the listing of the Deweys and where I have had direct association with the status change.  These posts will tie in with a forthcoming Change Register giving detail to this list and its alterations since publication in the Mountain tables book.

Bryn-llus (SJ 085 408) during the Leica 530 survey that confirmed this hill's Dewey status

The 500-Metre Tops of England and Wales are affectionately known after their hill list compiler; Michael Dewey.  This list mixes metric and imperial height in its criteria to bookend up to the 2000ft height band and takes in all hills in England, Isle of Man and Wales that are 500m and above and below 2000ft (609.6m) in height that have 30m minimum drop.

This list formed one of a number of lists that appeared in the Mountain tables book published by Constable in 1995 and at the time of publication comprised 373 hills with 164 in England, 5 in the Isle of Man and 204 in Wales.  The Deweys have undergone extensive revision since first publication with the initial stages forming the basis of this revision given below:


1995    Mountain tables published by Constable with 373 hills listed as Deweys.

April 2000    Strider (LDWA quarterly booklet) publishes contact details for David Purchase and Myrddyn Phillips who have found and list 24 and 14 possible new 500m tops respectively.

It was expanded versions of the above two lists that formed the basis of the next publication:

25th May 2000    List of Possible 500 Metre Tops by Michael Dewey listing 44 hills.

David Purchase expands his Additional Dewey 500m Hills and Myrddyn Phillips produces lists of English 500m hills to measure and Welsh 500m hills to measure.

These lists formed the basis of the next publication:

29th June 2000    Possible/Probable 500’s by Michael Dewey listing 77 hills.  Michael adopts following protocol; if one person proposes that a top should qualify as a 500 by personal survey, and is then confirmed by a second person, it should then be promoted to the main list.

April 2002    The 500+ Tops of England and Wales – The ‘New Deweys’ published in the Strider booklet and listing 66 new qualifying hills.

25th May 2006    Rob Woodall republishes Michael’s main and possible/probable lists on the RHB Yahoo group file database. 

Mountain tables by Michael Dewey

The details for this addition appear below:

The name the hill is listed by and its composition in the Deweys is Bryn-llus, and it is adjoined to the Y Berwyn group of hills which are situated in the south-eastern part of north Wales, and it is positioned with the A5 road to its north and the B4401 road to its west, and has the town of Corwen towards the north north-west.

The remains of Liberty Hall on Bryn-llus

This hill was not included in the original 1995 Constable publication, but with a 549m summit spot height and a 519m bwlch spot height that appear on the Ordnance Survey 1:25,000 Explorer map, this hill has a minimum of 30m of drop according to contemporary Ordnance Survey maps and therefore was an automatic entry to the listing of Deweys. 

Extract from the Ordnance Survey 1:25,000 Explorer map

The above was noted by Myrddyn Phillips and these details were forwarded to the list author; Michael Dewey and the hill was added to the list on the 3rd May 2000. 

Graham Jackson and John Barnard at the bwlch of Bryn-llus during the Leica 530 survey

As the 30m drop value is the minimum required for qualification to the Deweys list this hill was prioritised for a GNSS survey and this took place on the 26th January 2010.  The summit and bwlch of this hill were surveyed by John Barnard, Graham Jackson and Myrddyn Phillips using a Leica 530 with 60 minutes of data gathered at each point.  The survey resulted in a 547.8m summit height and a 516.1m bwlch height, with these values giving this hill 31.7m of drop and this hill’s retention as a Dewey.  


The full details for the hill are:

Name:  Bryn-llus

OS 1:50,000 map:  125

OS 1:25,000 map:  255

Summit Height:  547.8m (Leica 530)

Summit Grid Reference:  SJ 08564 40894 (Leica 530)

Bwlch Height:  516.1m (Leica 530)

Bwlch Grid Reference:  SJ 09433 40520 (Leica 530)

Drop:  31.7m (Leica 530)


Myrddyn Phillips (April 2020)






Mapping Mountains - Hill Reclassifications - The 500-Metre Tops of England and Wales - Deweys

Craig Llyn Du (SH 655 295) – Dewey addition (5th reclassification)


This is one in a series of retrospective Hill Reclassification posts that detail hills whose status has altered in the listing of the Deweys and where I have had direct association with the status change.  These posts will tie in with a forthcoming Change Register giving detail to this list and its alterations since publication in the Mountain tables book.

Craig Llyn Du (SH 655 295)

The 500-Metre Tops of England and Wales are affectionately known after their hill list compiler; Michael Dewey.  This list mixes metric and imperial height in its criteria to bookend up to the 2000ft height band and takes in all hills in England, Isle of Man and Wales that are 500m and above and below 2000ft (609.6m) in height that have 30m minimum drop.

This list formed one of a number of lists that appeared in the Mountain tables book published by Constable in 1995 and at the time of publication comprised 373 hills with 164 in England, 5 in the Isle of Man and 204 in Wales.  The Deweys have undergone extensive revision since first publication with the initial stages forming the basis of this revision given below:


1995    Mountain tables published by Constable with 373 hills listed as Deweys.

April 2000    Strider (LDWA quarterly booklet) publishes contact details for David Purchase and Myrddyn Phillips who have found and list 24 and 14 possible new 500m tops respectively.

It was expanded versions of the above two lists that formed the basis of the next publication:

25th May 2000    List of Possible 500 Metre Tops by Michael Dewey listing 44 hills.

David Purchase expands his Additional Dewey 500m Hills and Myrddyn Phillips produces lists of English 500m hills to measure and Welsh 500m hills to measure.

These lists formed the basis of the next publication:

29th June 2000    Possible/Probable 500’s by Michael Dewey listing 77 hills.  Michael adopts following protocol; if one person proposes that a top should qualify as a 500 by personal survey, and is then confirmed by a second person, it should then be promoted to the main list.

April 2002    The 500+ Tops of England and Wales – The ‘New Deweys’ published in the Strider booklet and listing 66 new qualifying hills.

25th May 2006    Rob Woodall republishes Michael’s main and possible/probable lists on the RHB Yahoo group file database. 


Mountain tables by Michael Dewey

The details for this addition appear below:

The name the hill is listed by in the Deweys is Craig Llyn Du, and it is adjoined to the Rhinogydd group of hills which are situated in the western part of north Wales, and it is positioned with the A496 road to its north, west and south, and the A470 road to its east, and has the village of Llandanwg towards the west.

The Name: Craig Llyn Du is an invented name based on the hill’s rocky profile and its proximity to Llyn Du which is positioned immediately to the south of this hill’s summit.  The details for this hill were forwarded my Myrddyn Phillips to Rob Woodall under the name of Rhinog Fawr North Top, Rob replied with the suggested name of Craig Llyn Du (letter dated 19.04.00).  Rob then forwarded the details to Michael.

This hill was not included in the original 1995 Constable publication, but with two small 550m ring contours that appear on the Ordnance Survey 1:25,000 Explorer map and bwlch contouring between 510m – 520m that appear on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map, this hill has a minimum of 30m of drop according to contemporary Ordnance Survey maps and therefore was an automatic entry to the listing of Deweys. 

Extract from the Ordnance Survey 1:25,000 Explorer map

The above was noted by Myrddyn Phillips who passed the detail on to Rob Woodall, who forwarded the detail to the list author; Michael Dewey and the hill was added to the list on the 3rd May 2000 under the name of Craig Llyn Du.


The full details for the hill are:

Name:  Craig Llyn Du

OS 1:50,000 map:  124

OS 1:25,000 map:  18

Summit Height:  c 553m (interpolation)

Summit Grid Reference:  SH 65552 29569 (hand-held GPS via DoBIH)

Bwlch Height:  c 518m (interpolation)

Bwlch Grid Reference:  SH 65371 29438 (interpolation)

Drop:  c 35m (interpolation)


Myrddyn Phillips (April 2020)







Mapping Mountains - Hill Reclassifications - The 500-Metre Tops of England and Wales - Deweys

Orddu (SH 963 423) – Dewey addition (4th reclassification)


This is one in a series of retrospective Hill Reclassification posts that detail hills whose status has altered in the listing of the Deweys and where I have had direct association with the status change.  These posts will tie in with a forthcoming Change Register giving detail to this list and its alterations since publication in the Mountain tables book.

Orddu (SH 963 423)

The 500-Metre Tops of England and Wales are affectionately known after their hill list compiler; Michael Dewey.  This list mixes metric and imperial height in its criteria to bookend up to the 2000ft height band and takes in all hills in England, Isle of Man and Wales that are 500m and above and below 2000ft (609.6m) in height that have 30m minimum drop.

This list formed one of a number of lists that appeared in the Mountain tables book published by Constable in 1995 and at the time of publication comprised 373 hills with 164 in England, 5 in the Isle of Man and 204 in Wales.  The Deweys have undergone extensive revision since first publication with the initial stages forming the basis of this revision given below:


1995    Mountain tables published by Constable with 373 hills listed as Deweys.

April 2000    Strider (LDWA quarterly booklet) publishes contact details for David Purchase and Myrddyn Phillips who have found and list 24 and 14 possible new 500m tops respectively.

It was expanded versions of the above two lists that formed the basis of the next publication:

25th May 2000    List of Possible 500 Metre Tops by Michael Dewey listing 44 hills.

David Purchase expands his Additional Dewey 500m Hills and Myrddyn Phillips produces lists of English 500m hills to measure and Welsh 500m hills to measure.

These lists formed the basis of the next publication:

29th June 2000    Possible/Probable 500’s by Michael Dewey listing 77 hills.  Michael adopts following protocol; if one person proposes that a top should qualify as a 500 by personal survey, and is then confirmed by a second person, it should then be promoted to the main list.

April 2002    The 500+ Tops of England and Wales – The ‘New Deweys’ published in the Strider booklet and listing 66 new qualifying hills.

25th May 2006    Rob Woodall republishes Michael’s main and possible/probable lists on the RHB Yahoo group file database. 


Mountain tables by Michael Dewey

The details for this addition appear below:

The name the hill is listed by in the Deweys is Orddu, and it is adjoined to the Arenig group of hills which are situated in the north-western part of north Wales, and it is positioned with the A5 road to its north-east, the B4501 road to its west and the A494 road to its south-east, and has the town of Y Bala towards the south south-west.

This hill was not included in the original 1995 Constable publication, but with a 555m summit spot height that appears on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map and bwlch contouring between 520m – 530m on the 1:50,000 Landranger and 1:25,000 Explorer map, the interpolated drop value was estimated sufficient for this hill to be a new Dewey. 

Extract from the Ordnance Survey 1:25,000 Explorer map

The above detail was noted by David Purchase and Myrddyn Phillips who worked independently but also exchanged all data.  On the 29th March 2000 and the 16th April 2000 Myrddyn Phillips conducted a basic levelling survey (BLS) of this hill, resulting in the average of these two surveys being 112½ft / 34.3m of drop.  These details were forwarded to the list author; Michael Dewey and the hill was added to the list on the 3rd May 2000.

Extract from the Magic Maps website

Since the inclusion of this hill in the Dewey list the Ordnance Survey Vector Map Local hosted on the Geograph website and which is entitled the Interactive Coverage Map became available online.  This mapping had many spot heights not on other publicly available Ordnance Survey maps and gives a 521m spot height on the area of this hill’s bwlch, and when coupled with the 555m summit spot height these values give this hill 34m of drop.  The 521m spot height is also shown on Ordnance Survey data that appears on the Magic Maps website.


Gathering data at the summit of Orddu

Gathering data at the bwlch of Orddu

As the drop from the BLS survey and summit and bwlch spot heights is close to the minimum 30m qualifying drop value, this hill was prioritised for a GNSS survey, and this took place on the 19th January 2020.  The summit and bwlch of this hill were surveyed by Myrddyn Phillips and Aled Williams using a Trimble GeoXH 6000, resulting in a 553.8m summit height and a 520.5m bwlch height, with these values giving this hill 33.3m of drop and confirming its Dewey status.


The full details for the hill are:

Name:  Orddu

OS 1:50,000 map:  125

OS 1:25,000 map:  18

Summit Height:  553.8m (converted to OSGM15, Trimble GeoXH 6000)

Summit Grid Reference:  SH 96338 42337 (Trimble GeoXH 6000)

Bwlch Height:  520.5m (converted to OSGM15, Trimble GeoXH 6000)

Bwlch Grid Reference:  SH 95886 42428 (Trimble GeoXH 6000)

Drop:  33.3m (Trimble GeoXH 6000)


Myrddyn Phillips (April 2020) 






Mapping Mountains - Hill Reclassifications - The 500-Metre Tops of England and Wales - Deweys

THIS HILL HAS SUBSEQUENTLY BEEN DELETED FROM THE DEWEY LIST

Iwerddon (SH 688 482) – Dewey addition (3rd reclassification)


This is one in a series of retrospective Hill Reclassification posts that detail hills whose status has altered in the listing of the Deweys and where I have had direct association with the status change.  These posts will tie in with a forthcoming Change Register giving detail to this list and its alterations since publication in the Mountain tables book.

Iwerddon (SH 688 482) during the line survey that subsequently deleted this hill from the list of Deweys

The 500-Metre Tops of England and Wales are affectionately known after their hill list compiler; Michael Dewey.  This list mixes metric and imperial height in its criteria to bookend up to the 2000ft height band and takes in all hills in England, Isle of Man and Wales that are 500m and above and below 2000ft (609.6m) in height that have 30m minimum drop.

This list formed one of a number of lists that appeared in the Mountain tables book published by Constable in 1995 and at the time of publication comprised 373 hills with 164 in England, 5 in the Isle of Man and 204 in Wales.  The Deweys have undergone extensive revision since first publication with the initial stages forming the basis of this revision given below:


1995    Mountain tables published by Constable with 373 hills listed as Deweys.

April 2000    Strider (LDWA quarterly booklet) publishes contact details for David Purchase and Myrddyn Phillips who have found and list 24 and 14 possible new 500m tops respectively.

It was expanded versions of the above two lists that formed the basis of the next publication:

25th May 2000    List of Possible 500 Metre Tops by Michael Dewey listing 44 hills.

David Purchase expands his Additional Dewey 500m Hills and Myrddyn Phillips produces lists of English 500m hills to measure and Welsh 500m hills to measure.

These lists formed the basis of the next publication:

29th June 2000    Possible/Probable 500’s by Michael Dewey listing 77 hills.  Michael adopts following protocol; if one person proposes that a top should qualify as a 500 by personal survey, and is then confirmed by a second person, it should then be promoted to the main list.

April 2002    The 500+ Tops of England and Wales – The ‘New Deweys’ published in the Strider booklet and listing 66 new qualifying hills.

25th May 2006    Rob Woodall republishes Michael’s main and possible/probable lists on the RHB Yahoo group file database. 

Mountain tables by Michael Dewey


The details for this addition appear below:

The name the hill is listed by in the Deweys is Iwerddon, and it is adjoined to the Moelwynion group of hills which are situated in the north-western part of north Wales, and it is positioned with the A498 road to its north-west and the A470 road to its east, and has the town of Blaenau Ffestiniog towards the south south-east.

This hill was not included in the original 1995 Constable publication, but with a 583m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and bwlch contouring between 550m - 560m that appears on the 1:50,000 Landranger and 1:25,000 Explorer map, the interpolated drop value was estimated sufficient for this hill to be a potential new Dewey.

Extract from the Ordnance Survey 1:25,000 Explorer map

The above detail was noted by David Purchase and Myrddyn Phillips who worked independently but also exchanged all data.  These details were forwarded to the list author; Michael Dewey and the hill was added to the list on the 3rd May 2000.  Subsequently Myrddyn Phillips conducted a basic levelling survey of this hill on the 5th May 2000 without prior knowledge of its recent inclusion, resulting in the hill considered to have just over 30m of drop.


The full details for the hill are:

Name:  Iwerddon

OS 1:50,000 map:  115

OS 1:25,000 map:  17

Summit Height:  583m (spot height)

Summit Grid Reference:  SH 68822 48217 (hand-held GPS via DoBIH)

Bwlch Height:  553m (relative to spot heighted summit and basic levelling survey drop)

Bwlch Grid Reference:  SH 68409 47880 (hand-held GPS via DoBIH)

Drop:  30m (basic levelling survey)


Myrddyn Phillips (April 2020)






Mapping Mountains - Hill Reclassifications - The 500-Metre Tops of England and Wales - Deweys

Foel-fras (SH 728 481) – Dewey addition (2nd reclassification)


This is one in a series of retrospective Hill Reclassification posts that detail hills whose status has altered in the listing of the Deweys and where I have had direct association with the status change.  These posts will tie in with a forthcoming Change Register giving detail to this list and its alterations since publication in the Mountain tables book.

Foel-fras (SH 728 481)

The 500-Metre Tops of England and Wales are affectionately known after their hill list compiler; Michael Dewey.  This list mixes metric and imperial height in its criteria to bookend up to the 2000ft height band and takes in all hills in England, Isle of Man and Wales that are 500m and above and below 2000ft (609.6m) in height that have 30m minimum drop.

This list formed one of a number of lists that appeared in the Mountain tables book published by Constable in 1995 and at the time of publication comprised 373 hills with 164 in England, 5 in the Isle of Man and 204 in Wales.  The Deweys have undergone extensive revision since first publication with the initial stages forming the basis of this revision given below:


1995    Mountain tables published by Constable with 373 hills listed as Deweys.

April 2000    Strider (LDWA quarterly booklet) publishes contact details for David Purchase and Myrddyn Phillips who have found and list 24 and 14 possible new 500m tops respectively.

It was expanded versions of the above two lists that formed the basis of the next publication:

25th May 2000    List of Possible 500 Metre Tops by Michael Dewey listing 44 hills.

David Purchase expands his Additional Dewey 500m Hills and Myrddyn Phillips produces lists of English 500m hills to measure and Welsh 500m hills to measure.

These lists formed the basis of the next publication:

29th June 2000    Possible/Probable 500’s by Michael Dewey listing 77 hills.  Michael adopts following protocol; if one person proposes that a top should qualify as a 500 by personal survey, and is then confirmed by a second person, it should then be promoted to the main list.

April 2002    The 500+ Tops of England and Wales – The ‘New Deweys’ published in the Strider booklet and listing 66 new qualifying hills.

25th May 2006    Rob Woodall republishes Michael’s main and possible/probable lists on the RHB Yahoo group file database. 


Mountain tables by Michael Dewey

The details for this addition appear below:

The name the hill is listed by and its composition in the Deweys is Foel-fras, and it is adjoined to the Arenig group of hills which are situated in the north-western part of north Wales, and it is positioned with the A470 road to its north and west, the B4407 road to its south-east and the A5 road to its east north-east, and has the village of Dolwyddelan towards the north.

This hill was not included in the original 1995 Constable publication, but with a 586m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and bwlch contouring between 550m – 560m on the 1:50,000 Landranger and 1:25,000 Explorer map, the drop of this hill was estimated from bwlch interpolation to have the minimum of 30m required for qualification as a Dewey. 

Extract from the Ordnance Survey 1:25,000 Explorer map

The above detail was noted by David Purchase and Myrddyn Phillips who worked independently but also exchanged all data.  These details were forwarded to the list author; Michael Dewey and the hill was added to the list on the 3rd May 2000.  Subsequently Myrddyn Phillips conducted a basic levelling survey of this hill on the 4th May 2000 without prior knowledge of its recent inclusion, resulting in the hill having over 30m of drop.


The full details for the hill are:

Name:  Foel-fras

OS 1:50,000 map:  115

OS 1:25,000 map:  18

Summit Height:  586m (spot height)

Summit Grid Reference:  SH 72803 48165 (hand-held GPS via DoBIH)

Bwlch Height:  c 556m (interpolation)

Bwlch Grid Reference:  SH 72282 48254 (interpolation)

Drop:  c 30m (spot height summit and interpolated bwlch)


Myrddyn Phillips (April 2020)






Mapping Mountains - Hill Reclassifications - The 500-Metre Tops of England and Wales - Deweys


Craig y Moch (Craig Fach) (SH 634 552) – Dewey addition (1st reclassification)


This is one in a series of retrospective Hill Reclassification posts that detail hills whose status has altered in the listing of the Deweys and where I have had direct association with the status change.  These posts will tie in with a forthcoming Change Register giving detail to this list and its alterations since publication in the Mountain tables book.

The hill listed as Craig y Moch (Craig Fach) (SH 634 552) in the Deweys

The 500-Metre Tops of England and Wales are affectionately known after their hill list compiler; Michael Dewey.  This list mixes metric and imperial height in its criteria to bookend up to the 2000ft height band and takes in all hills in England, Isle of Man and Wales that are 500m and above and below 2000ft (609.6m) in height that have 30m minimum drop.

This list formed one of a number of lists that appeared in the Mountain tables book published by Constable in 1995 and at the time of publication comprised 373 hills with 164 in England, 5 in the Isle of Man and 204 in Wales.  The Deweys have undergone extensive revision since first publication with the initial stages forming the basis of this revision given below:


1995    Mountain tables published by Constable with 373 hills listed as Deweys.

April 2000    Strider (LDWA quarterly booklet) publishes contact details for David Purchase and Myrddyn Phillips who have found and list 24 and 14 possible new 500m tops respectively.

It was expanded versions of the above two lists that formed the basis of the next publication:

25th May 2000    List of Possible 500 Metre Tops by Michael Dewey listing 44 hills.

David Purchase expands his Additional Dewey 500m Hills and Myrddyn Phillips produces lists of English 500m hills to measure and Welsh 500m hills to measure.

These lists formed the basis of the next publication:

29th June 2000    Possible/Probable 500’s by Michael Dewey listing 77 hills.  Michael adopts following protocol; if one person proposes that a top should qualify as a 500 by personal survey, and is then confirmed by a second person, it should then be promoted to the main list.

April 2002    The 500+ Tops of England and Wales – The ‘New Deweys’ published in the Strider booklet and listing 66 new qualifying hills.

25th May 2006    Rob Woodall republishes Michael’s main and possible/probable lists on the RHB Yahoo group file database. 


Mountain tables by Michael Dewey

The details for this addition appear below:

The name the hill is listed by in the Deweys is Craig y Moch (Craig Fach), and it is adjoined to the Yr Wyddfa group of hills which are situated in the north-western part of north Wales, and it is positioned with the A4086 road to its north, the A4085 road to its west and the A498 road to its south-east, and has the village of Beddgelert towards the south-west.

The Name: Craig y Moch is an invented name partly transposed from the bwlch to the west of this hill’s summit.  This is the originating name in the Dewey list with the use of the bracketed Craig Fach a later addition with this name relating to a near crag and not necessarily the hill.

This hill was not included in the original 1995 Constable publication, but with a 609m summit spot height that appears on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map and a 569m bwlch spot height that appears on the Ordnance Survey 1:25,000 Explorer map, this hill had 40m of drop according to contemporary Ordnance Survey maps and therefore was an automatic entry to the listing of Deweys.

Extract from the Ordnance Survey 1:25,000 Explorer map

The above detail was noted by David Purchase and Myrddyn Phillips who worked independently but also exchanged all data, with David having assessed the hill’s qualification on site.  These details were forwarded to the list author; Michael Dewey and the hill was added to the list on the 3rd May 2000 under the name of Craig y Moch, with the bracketed Craig Fach being a later addition.

Surveying the summit of the hill listed as Craig y Moch (Craig Fach) in the Deweys

As its 609m summit sp0t height is near the benchmark height of 2000ft (609.6m) this hill was prioritised for a GNSS survey by John Barnard who approached Leica Geosystems suggesting that a joint survey with the fledgling team of G&J Surveys could take place.  Leica Geosystems were enthusiastic for this to happen and the hill was surveyed on the 11th August 2008 by James Whitworth of Leica Geosystems using a Leica SmartRover 1200, resulting in a 608.8m summit height and this hill’s retention as a Dewey.


The full details for the hill are:

Name:  Craig y Moch (Craig Fach)

OS 1:50,000 map:  115

OS 1:25,000 map:  17

Summit Height:  608.8m (Leica SmartRover 1200)

Summit Grid Reference:  SH 63495 55248 (Leica SmartRover 1200)

Bwlch Height:  569m (spot height)

Bwlch Grid Reference:  SH 63329 55253 (spot height)

Drop:  40m (Leica SmartRover 1200 summit and spot height bwlch)


Myrddyn Phillips (April 2020)




No comments: