Change Register - The Deweys of Wales

Change Register

The 500-Metre Tops of England and Wales – the Deweys

The Deweys of Wales

In 1995 Constable published a book entitled Mountain tables authored by Michael Dewey.  The book documents a number of hill lists with this Change Register concentrating on one of these lists; The 500-Metre Tops of England and Wales, which for convenience has been split in to its component parts with the changes since first publication to the Welsh 500-Metre Tops detailed below and their English counterparts detailed in a separate Change Register, with the total for the Isle of Man 500-Metre Tops remaining unaltered.

The 500-Metre Tops of England and Wales is compiled by Michael Dewey and the list is now known affectionately after its compiler as the Deweys.  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.

When the list was first published it 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 over 90 reclassifications to the list (58 in Wales and 39 in England at the time of this Change Register publication).  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.

For hill baggers who visit the Welsh hills the Deweys form an important part of their hill walking, as many baggers natural instinct is to visit the higher 2000ft hills first; these take in the category of Hewitts (P30) and Nuttalls (P15), but after completion of one if not both of these lists, what comes next; the natural progression is the Deweys.

For those people who have completed an ascent of each listed hill they would have visited all summits in Wales at and above 500m and below 2000ft (609.6m) in height that have a minimum drop of 30m on all sides.  These hills take in the majority of upland areas in Wales from the northern Snowdonia summits and the Mynydd Hiraethog and Bryniau Clwyd hills to the great swathe of remote and bleak wilderness of the central hills to the southern Mynydd Preseli, Bannau Brycheiniog and the hills of the Cymoedd.  Each and every hill can leave memories that refresh the soul and body, and for many it is the list of The 500-Metre Tops of England and Wales in the Mountain tables book that has taken them on a journey through some of the most beautiful landscape that Britain has to offer.

The majority of changes to this list took place in the years 2000 and 2001, with over 70 of the current 97 additions and deletions taking place during a 20 month period, and this was led by three main people; David Purchase, Myrddyn Phillips and Rob Woodall, who all worked closely together swapping information and co-ordinating this with Michael Dewey who instigated all necessary alterations.

During this period a number of hills appeared in the list twice with their details having been duplicated; these include Priddellau (SN 854 677) and Mynydd Rhyd-galed / Tarrenhendre East Top (SH 699 043) with the latter appearing twice in the same updated list under two different names.  Cripiau South Top (SN 802 828) was also added to the list under the grid reference for its non-Dewey and lower adjacent hill of Cripiau (SN 798 836).  The Change Register does not document such transposed inclusions.

However, the Change Register does document the inclusion and subsequent deletion of Esgair y Maesnant (SN 832 862) and Foel Cynfal (SH 749 395), as both hills for a short period of time were listed as Deweys and their details were not transposed. 

Where more than one hill was added to the list on the same day these hills appear in the Change Register listed numerically, from highest to lowest in receding order justifying the latest changes always appearing toward the top of the Register.

Where the exact date of inclusion and / or deletion is not known and where these have involved a surveyed hill, the date of survey is given in the Change Register.  Where other exact dates of inclusion and / or deletion are not known a Pre date or month date is used.  

Since this lists’ first publication in 1995 the diligence of map study and the influx of independent surveyors and the use of LIDAR have added and deleted a number of hills.  This Change Register endeavours to document these changes and give due accreditation to the people involved.

Michael Dewey died on the 5^th November 2022.  His wife; Gillian wished for this list to be carried on and made provision for it to be co-authored by Myrddyn Phillips.  Michael will always be the compiler and originator, it’s just that he’s now got a co-author to safeguard and carry this list on.  Hopefully this list will retain the name of the Deweys; an affectionate moniker given it by hill baggers, as this is an appropriate testament to what Michael created and a legacy to remember Michael by.

The Change Register to the Deweys of Wales since the 1995 Mountain tables publication appears below with the hills listed in receding order under the hill name used by Michael Dewey:

Change Register

The Deweys of Wales

Foel y Geifr    515.6m at SH 71634 05092 (Deleted from list:  26^th May 2023)

LIDAR image of Foel y Geifr (SH 716 050)

This hill was deleted from the list of Deweys on the 26^th May 2023 due to LIDAR analysis instigated from detail produced by Joe Nuttall in his surface analysis progamme, with subsequent LIDAR analysis conducted by George Gradwell of the DoBIH team and independently by Aled Williams.  This hill was not included in the Mountain tables book published by Constable in 1995, 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 of this hill was estimated sufficient for it to be a potential new Dewey.  This prompted a basic levelling survey conducted by Myrddyn Phillips resulting in its inclusion.  Its subsequent deletion is due to LIDAR analysis, resulting in a 515.6m summit height and a 486.8m bwlch height, with these values giving this hill 28.8m of drop.  Welsh Dewey total decreases by one and confirmed as 240.

5^th November 2022 – Michael Dewey dies with provision made by his wife Gillian for this list to carry on and become co-authored by Myrddyn Phillips. 

Y Drum    579.1m at SJ 08247 37893 (Added to list:  28^th November 2020) 

Y Drum (SJ 082 378)

This hill was not included in the Mountain tables book published by Constable in 1995, but was subsequently included due to a Trimble GeoXH 6000 survey.  It was previously listed with 28m of drop based on the 579m summit spot height and the 551m bwlch spot height that appear on the Ordnance Survey 1:25,000 Explorer map.  Since the 1995 publication of this list there have been a number of Ordnance Survey maps made available online, some of these are historic such as the series of Six-Inch maps on the National Library of Scotland website, whilst others are current and digitally updated such as the mapping on the OS Maps website.  This is the replacement for OS Get-a-map and until recent times had contours at 5m intervals that were proving consistently more accurate compared to the 5m contours that sometimes appear on Ordnance Survey 1:25,000 Explorer maps and used to appear on the online Vector Map Local.  This mapping showed bwlch contouring between 545m – 550m, with interpolation giving an estimated c 549m height and an estimated c 30m of drop.  Therefore, it was known that this hill was a potential new Dewey.  With this information the hill was prioritised for a GNSS survey and this took place on the 26^th November 2020.  The summit and bwlch of this hill were surveyed using a Trimble GeoXH 6000 in the company of Aled Williams and Mark Trengove, resulting in a 579.1m summit height and a 549.0m bwlch height, with these values giving this hill 30.1m of drop.  These details were forwarded to Michael Dewey and the hill was subsequently added to his list on the 28^th November 2020.  Welsh Dewey total increases by one and confirmed as 241.

Twr Pen-cyrn    528.9m at SO 20281 14491 (Deleted from list:  25^th June 2020) 

LIDAR summit image of Twr Pen-cyrn (SO 202 144)

This hill was not included in the Mountain tables book published by Constable in 1995 and was one of six hills added in what is likely to be early April 2000 and which formed the first batch of additions to Michael Dewey’s online website list of The 500-Metre Tops of England and Wales.  Its subsequent deletion is due to LIDAR analysis initially conducted by Aled Williams with these details forwarded to Michael Dewey in February 2017 and subsequently by Myrddyn Phillips with Michael then consulted, resulting in a 528.9m summit height and a 499.7m bwlch height, with these values giving this hill 29.3m of drop and its deletion from Dewey status.  Welsh Dewey total decreases by one and confirmed as 240.

Cefn Cyfarwydd    501.7m at SH 75201 63067 (Added to list:  19^th February 2019)

Cefn Cyfarwydd (SH 752 630)

This hill was included in Michael Dewey’s list of the The 500-Metre Tops of England and Wales due to a Trimble GeoXH 6000 survey and was not included in the Mountain tables book published by Constable in 1995, as with a 503m summit spot height and a 477m bwlch spot height that appear on the Ordnance Survey 1:25,000 Explorer map it was accepted that the hill had under 30m of drop.  Since the 1995 publication of this list there have been a number of Ordnance Survey maps made available online, some of these are historic such as the series of Six-Inch maps on the National Library of Scotland website, whilst others are current and digitally updated such as the mapping on the OS Maps website.  This is the replacement for OS Get-a-map and has contours at 5m intervals which are proving consistently more accurate compared to the 5m contours that sometimes appear on Ordnance Survey 1:25,000 Explorer maps and used to appear on the online Vector Map Local.  This mapping shows the 477m bwlch spot height to be positioned on a separate 475m contour ring implying that the height of this hill’s bwlch is substantially lower than 477m, with interpolation based on this contouring giving the hill an estimated c 30m of drop.  With this newly acquired information the hill was prioritised for a GNSS survey and this took place on the 17^th February 2019.  The summit and bwlch of this hill were surveyed by Myrddyn Phillips and Aled Williams using a Trimble GeoXH 6000 resulting in a 501.7m summit height and a 471.0m bwlch height, with these values giving this hill 30.7m of drop.  These details were forwarded to the list author; Michael Dewey and the hill was subsequently added to his list on 19^th February 2019.  Welsh Dewey total increases by one and confirmed as 241.

Twynwalter    502.1m at SN 82837 17506 (Deleted from list:  19^th February 2019)

The Trimble GeoXH 6000 gathering data at the summit of Twynwalter (SN 828 175)

This hill was deleted from Michael Dewey’s list of the The 500-Metre Tops of England and Wales due to a combination of a Trimble GeoXH 6000 summit survey and LIDAR analysis of its bwlch.  This hill was included in the Mountain tables book published by Constable in 1995 and listed with a 509m summit height which appears as a spot height on Ordnance Survey 1:25,000 Explorer maps and the Outdoor Leisure maps of the day.  Its drop value was later given as an estimated c 32m with its bwlch height an estimated c 477m based on interpolation of 10m contouring between 470m – 480m.  As the listed drop value was near the minimum 30m required for qualification to this list the hill was prioritised for a GNSS survey and this took place on the 10^th July 2014, with the summit of this hill surveyed by Myrddyn Phillips using a Trimble GeoXH 6000.  However, this was the last of many surveys conducted during the day that included visiting the remotest spot in mainland Wales as well as one of the remotest hills in Wales and lack of daylight hours dictated that only the summit could be surveyed.  The survey resulted in a 502.1m summit height, which is 6.9m lower than the 509m spot height on the Ordnance Survey 1:25,000 Explorer map.  The summit and bwlch heights for this hill were subsequently ascertained from LIDAR analysis initially conducted by Aled Williams and subsequently by Myrddyn Phillips, resulting in a bwlch height of 475.9m and when coupled with the 502.1m summit height from the Trimble GeoXH 6000 survey this gives the hill 26.25m of drop.  These details were forwarded to the list author; Michael Dewey and the hill was subsequently deleted from his list on 19^th February 2019.  Welsh Dewey total decreases by one and confirmed as 240.

Llechwedd Llwyd    535m at SH 83868 81410 (Deleted from list:  21^st August 2012)

This hill was deleted from Michael Dewey’s list of the The 500-Metre Tops of England and Wales due to map study conducted by Jim Bloomer.  This hill was not included in the Mountain tables book published by Constable in 1995, 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.  These details were noted by Myrddyn Phillips and once forwarded to the list author it was one of sixteen additions applied to the list by Michael Dewey on the 3^rd May 2000.  Its subsequent deletion is due to a 507m spot height that appeared on the bwlch area of this hill on the Ordnance Survey Vector Map Local hosted on the Geograph website and which was entitled the Interactive Coverage Map.  Welsh Dewey total decreases by one and confirmed as 241.

Cerrig yr Ieirch    511.0m at SH 75885 42509 (Deleted from list:  27^th October 2010)

Graham Jackson at the summit of Cerrig yr Ieirch (SH 758 425) with the Leica 530

This hill was deleted from Michael Dewey’s online website list of the The 500-Metre Tops of England and Wales due to a GNSS Leica 530 survey and it is the date of the survey that is used as that for the deletion date.  This hill was not included in the Mountain tables book published by Constable in 1995, but with a 513m 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.  These details were noted by Myrddyn Phillips and Rob Woodall, with Rob visiting the area of this hill’s bwlch to assess its candidacy for Dewey status and surveying from the bwlch toward a prominent boundary stone close to where the Ordnance Survey place the 490m contour on their maps.  The two then combined to undertake a basic levelling survey of this hill on the 27^th October 2001.  The survey repeated Rob’s measurement from the bwlch to a path just below the boundary stone to where the 490m contour is placed.  With 23m then added to the result to compensate for the height difference between the 513m summit spot height and the 490m contour, resulting in 100ft / 30.5m of drop.  These details were forwarded to the list author; Michael Dewey and it was one of four hills (all in Wales) added the list on 2^nd November 2001.  As the result from the basic levelling survey was near the minimum 30m of drop required for qualification to Dewey status this hill was prioritised for a GNSS survey and this took place on the 27^th October 2010.  The summit and bwlch of this hill were surveyed by John Barnard, Graham Jackson and Myrddyn Phillips using a Leica 530 resulting in a 511.0m summit height and a 481.9m bwlch height, with these values giving this hill 29.2m of drop and its subsequent deletion from the list of Deweys.  Welsh Dewey total decreases by one and confirmed as 242.

Iwerddon    583m at SH 68822 48217 (Deleted from list:  11^th March 2010)

Iwerddon (SH 688 482)

This hill was deleted from Michael Dewey’s online website list of the The 500-Metre Tops of England and Wales due to a level and staff line survey and it is the date of the survey that is used as that for the deletion date.  This hill was not included in the Mountain tables book published by Constable in 1995, but with a 583m summit spot height and bwlch contouring between 550m – 560m that appear on the Ordnance Survey 1:25,000 Explorer map this hill was judged from contour interpolation to have sufficient drop to be included as a Dewey.  These details were noted by David Purchase and Myrddyn Phillips who worked independently but also exchanged all data and these details were forwarded to the list author; Michael Dewey and it was one of sixteen hills added to the list on the 3^rd May 2000.  Subsequently Myrddyn Phillips conducted a basic levelling survey of this hill on the 5^th May 2000 without prior knowledge of its recent inclusion, resulting in the hill considered to have just over 30m of drop.  Its deletion from this list is due to a level and staff line survey conducted by John Barnard and Myrddyn Phillips, resulting in 25.2m of drop.  Welsh Dewey total decreases by one and confirmed as 243.

Mynydd Graig Goch    609.8m at SH 49732 48518 (Deleted from list:  11^th August 2008)  

Mynydd Graig Goch (SH 497 485)

This hill was deleted from Michael Dewey’s online website list of the The 500-Metre Tops of England and Wales and it is the date of the survey that is used as that for the deletion date.  This hill was included in the Mountain tables book published by Constable in 1995 as it had a 609m summit spot height that appeared on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer maps of the day and easily qualified for Dewey status with its drop.  The confirmation of this hill’s reclassification from Dewey to Hewitt status took place on the 19^th September 2008 at a press conference held in the Oakeley Room at Plas Tan-y-bwlch, Maentwrog in Snowdonia.  The survey that resulted in this hill’s reclassification was conducted in conjunction with Leica Geosystems, Clwb Mynydda Cymru and the Snowdonia National Park Authority, with Leica Geosystems’ representative; James Whitworth being the surveyor who operated the Leica 1200.  Present on the survey were John Barnard, Graham Jackson, Myrddyn Phillips, Dewi Jones, Harold Morris, Anne Nuttall, John Nuttall and James Whitworth.  This was the third occasion that Differential GPS equipment had been used outside of the Ordnance Survey to determine the accurate height of a hill, with The Munro Society pioneering its use having commissioned CMCR Ltd to survey two hills in Scotland for Munro status.  The resulting reclassification of Mynydd Graig Goch made headlines on national television, radio and in national newspapers.  Welsh Dewey total decreases by one and confirmed as 244.

Domen-ddu    553m at SO 01693 78268 (Deleted from list:  30^th June 2008)

During the line survey of Domen-ddu (SO 016 782)

This hill was deleted from Michael Dewey’s online website list of the The 500-Metre Tops of England and Wales and it is the date of the survey that is used as that for the deletion date.  This hill was not included in the Mountain tables book published by Constable in 1995, but was then added to the list (see below) in July / August 2004.  Its deletion from this list is due to a level and staff line survey conducted by John Barnard, Graham Jackson, Myrddyn Phillips and David Purchase, resulting in 24.3m of drop.  Once these details were forwarded to the list author; Michael Dewey, it was deleted from his list.  Welsh Dewey total decreases by one and confirmed as 245.

Mynydd Ceiswyn    604.9m at SH 77241 13902 (Deleted from list:  3^rd November 2007)

During the line survey of Mynydd Ceiswyn (SH 772 139)

This hill was deleted from Michael Dewey’s online website list of the The 500-Metre Tops of England and Wales and it is the date of the survey that is used as that for the deletion date.  This hill was not included in the Mountain tables book published by Constable in 1995, but was then added to the list (see below) on the 8^th January 2005.  Its deletion from this list is due to a level and staff line survey conducted by John Barnard, Graham Jackson and Myrddyn Phillips, resulting in 27.4m of drop.  Once these details were forwarded to the list author; Michael Dewey, it was deleted from his list.  The summit of this hill has now been surveyed by GNSS receiver and this was conducted by Alan Dawson on the 22^nd April 2019, using a Leica RX1250, resulting in a 604.9m height.  Welsh Dewey total decreases by one and confirmed as 246.

Mynydd Ceiswyn    605m at SH 77241 13902 (Added to list:  8^th January 2005)

THIS HILL HAS SUBSEQUENTLY BEEN DELETED FROM THE DEWEY LIST 

Mynydd Ceiswyn (SH 772 139)

This hill was one of three additions (two in Wales and one in England) to Michael Dewey’s online website list of the The 500-Metre Tops of England and Wales due to hand-help GPS readings taken by Stephen Walker, with all three additions subsequently deleted due to accurate surveying, and it was added to the list on the 8^th January 2005.  This hill was not included in the Mountain tables book published by Constable in 1995, and prior to its inclusion Myrddyn Phillips conducted a basic levelling survey of this hill on the 7^th May 2000, resulting in 95ft / 29.0m of drop.  This hill has subsequently been deleted from the Dewey list (see above).  Welsh Dewey total increases by one and confirmed as 247.

Domen-ddu    553m at SO 01693 78268 (Added to list:  July / August 2004)

THIS HILL HAS SUBSEQUENTLY BEEN DELETED FROM THE DEWEY LIST 

During the line survey that subsequently deleted this hill from Dewey status

This hill was one of three additions to Michael Dewey’s online website list of the The 500-Metre Tops of England and Wales due to hand-help GPS readings taken by Stephen Walker, with all three additions subsequently deleted due to accurate surveying.  As only the survey date of July / August 2004 is given in the accompanying Remarks column, this is used as that for the inclusion date.  This hill was not included in the Mountain tables book published by Constable in 1995, and prior to its inclusion Myrddyn Phillips with assistance from Eryl Selly and Stephen Hughes undertook a basic levelling survey of this hill on the 19^th September 2002, resulting in 81ft / 24.7m of drop.  This hill has subsequently been deleted from the Dewey list (see above).  Welsh Dewey total increases by one and confirmed as 246.

Cerrig yr Ieirch    513m at SH 75885 42509 (Added to list:  2^nd November 2001)

THIS HILL HAS SUBSEQUENTLY BEEN DELETED FROM THE DEWEY LIST 

Cerrig yr Ieirch (SH 758 425)

This was one of four hills (all in Wales) added to Michael Dewey’s online website list of the The 500-Metre Tops of England and Wales on the 2^nd November 2001.  This hill was not included in the Mountain tables book published by Constable in 1995, but with a 513m 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.  These details were noted by Myrddyn Phillips and Rob Woodall, with Rob visiting the area of this hill’s bwlch to assess its candidacy for Dewey status and surveying from the bwlch toward a prominent boundary stone close to where the Ordnance Survey place the 490m contour on their maps.  The two then combined to undertake a basic levelling survey of this hill on the 27^th October 2001.  The survey repeated Rob’s measurement from the bwlch to a path just below the boundary stone to where the 490m contour is placed.  With 23m then added to the result to compensate for the height difference between the 513m summit spot height and the 490m contour, resulting in 100ft / 30.5m of drop.  These details were forwarded to the list author; Michael Dewey and the hill was then added to the list.  This hill has subsequently been deleted from the Dewey list (see above).  Welsh Dewey total increases by one and confirmed as 245.

Craig y Benglog    525.3m at SH 80504 24416 (Added to list:  2^nd November 2001) 

Craig y Benglog

This was one of four hills added to Michael Dewey’s online website list of the The 500-Metre Tops of England and Wales on the 2^nd November 2001.  This hill was not included in the Mountain tables book published by Constable in 1995, but with an uppermost 520m ring contour 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.  These details were noted by Myrddyn Phillips, who was then joined by Rob Woodall to conduct a basic levelling survey of this hill on the 27^th October 2001, resulting in 110ft / 33.5m of drop.  These details were forwarded to the list author; Michael Dewey and the hill was added to the list on the 2^nd November 2001.  As this hill qualified for the Dewey list through a basic levelling survey it was prioritised for a GNSS survey, and this took place on the 26^th January 2009.  The summit and bwlch of this hill were surveyed by John Barnard, Graham Jackson and Myrddyn Phillips using a Leica 530, resulting in a 525.3m summit height and a 492.7m bwlch height, with these values giving this hill 32.6m of drop, and therefore confirming its Dewey status.  Welsh Dewey total increases by one and confirmed as 244.

Moel yr Wden    572.3m at SH 78012 35618 (Added to list:  2^nd November 2001) 

Moel yr Wden (SH 780 356)

This was one of four hills added to Michael Dewey’s online website list of the The 500-Metre Tops of England and Wales on the 2^nd November 2001.  This hill was not included in the Mountain tables book published by Constable in 1995, and with a 560m uppermost contour and bwlch contouring between 530m – 540m that appear on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map, and with the opposing 540m contours relatively close together, this hill was unlikely to have sufficient drop to qualify for this list.  These details were noted by Myrddyn Phillips, who then conducted a basic levelling survey of this hill on the 21^st July 2000, resulting in a surprising 112ft / 34.1m of drop.  As this result was at odds with Ordnance Survey contouring, Michael Dewey was informed, but it was decided not to promote this hill to Dewey status and wait for the result of a second survey.  The second basic levelling survey of this hill was conducted on the 27^th October 2001 by Myrddyn Phillips and Rob Woodall, resulting in the same drop value as the first; 112ft / 34.1m.  These details were forwarded to the list author; Michael Dewey and the hill was added to the list on the 2^nd November 2001.  As this hill qualified for the Dewey list through a basic levelling survey and as this was at odds with Ordnance Survey map contouring, it was prioritised for a line survey, and this took place on the 31^st March 2008.  The line survey consisted of two teams; Graham Jackson and Janet Jackson who concentrated on the drop value of Moel yr Wden, and John Barnard and Myrddyn Phillips who line surveyed from the 619m map heighted summit of Gallt y Daren (SH 778 344) to the bwlch position of Moel yr Wden, this resulted in 34.1m of drop with the summit of Moel yr Wden being 572.9m in height dependent upon the accuracy of the 619m spot height atop Gallt yr Daren.  This survey confirmed this hill’s Dewey status.  As the resulting height of Moel yr Wden was still at odds with its 560m uppermost contour on Ordnance Survey maps the hill was prioritised for a GNSS survey.  This was conducted by John Barnard, Graham Jackson and Myrddyn Phillips on the 25^th November 2008, resulting in a 572.3m summit height and a 538.2m bwlch height, with these values giving this hill 34.0m of drop, confirming that the contemporary Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map are missing an uppermost 570m ring contour.  Welsh Dewey total increases by one and confirmed as 243.

Cefn Coch    592.9m at SH 92310 26675 (Added to list:  2^nd November 2001) 

Cefn Coch (SH 923 266)

This was one of four hills added to Michael Dewey’s online website list of the The 500-Metre Tops of England and Wales on the 2^nd November 2001.  This hill was not included in the Mountain tables book published by Constable in 1995, but with a 594m summit spot height 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.  These details were noted by David Purchase and Myrddyn Phillips, and the latter was joined by Rob Woodall to then conduct a basic levelling survey of this hill on the 28^th October 2001, resulting in 103ft / 31.4m of drop.  These details were forwarded to the list author; Michael Dewey and the hill was then added to 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 gave a 565m spot height on the area of this hill’s bwlch, and when coupled with the 594m summit spot height these values gave this hill 29m of drop.  As this hill qualified for the Dewey list through a basic levelling survey and as the online Vector Map Local only gave the hill 29m of drop, it was prioritised for a GNSS survey, and this took place on the 19^th October 2016.  The summit and bwlch of this hill were surveyed by Alan Dawson and Myrddyn Phillips using a Leica RX1250 and Trimble GeoXH 6000 respectively, resulting in a 592.9m summit height and a 561.7m bwlch height, with these values giving this hill 31.25m of drop, and therefore confirming its Dewey status.  Welsh Dewey total increases by one and confirmed as 242.

Esgair Cloddiad    532.3m at SN 82471 57371 (Added to list:  28^th July 2001) 

The Trimble GeoXH 6000 gathering data at the summit of Esgair Cloddiad (SN 824 573)

This was one of eleven hills added on the 28^th July 2001 to Michael Dewey’s online website list of the The 500-Metre Tops of England and Wales.  This hill was not included in the Mountain tables book published by Constable in 1995, but with a 532m summit spot height adjoined to a triangulation pillar 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 as the 0pposing 500m ring contours are close together.  These details were noted by David Purchase and once forwarded to the list author; Michael Dewey, it was included in his list.  The summit of this hill was subsequently surveyed on the 29^th April 2023 by Aled Williams and Myrddyn Phillips using a Trimble GeoXH 6000 GNSS receiver, resulting in a 532.3m summit height and with a 500.8m bwlch height ascertained from LIDAR analysis conducted by Aled Williams, these values give this hill 31.5m of drop, confirming its Dewey status.  Welsh Dewey total increases by one and confirmed as 241.

Foel Uchaf    565m at SN 80274 91203 (Added to list:  28^th July 2001) 

This was one of eleven hills added to Michael Dewey’s online website list of the The 500-Metre Tops of England and Wales on the 28^th July 2001, and it was a reinstatement of a hill as Foel Uchaf was deleted from the Dewey list on the 11^th May 2000 having originally been listed in the Mountain tables book published by Constable in 1995, but with an 565m summit spot height and bwlch contouring between 530m – 540m 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 a Dewey.  These details were noted by David Purchase who assessed the hill’s qualification on site, and once forwarded to the list author; Michael Dewey, it was reinstated in his list.  Welsh Dewey total increases by one and confirmed as 240.

Esgair y Maesnant    503.6m at SN 83220 86275 (Deleted from list:  7^th August 2000)

The summit of Esgair y Maesnant (SN 832 862)

This was the third hill that Michael Dewey deleted from his listing of the The 500-Metre Tops of England and Wales.  Its deletion was confirmed in a letter received from the author dated 7^th August 2000.  The hill was inadvertently included in this list by Michael Dewey as it had been surveyed by Myrddyn Phillips on the 11^th July 2000 using a basic levelling technique as having 95½ft / 29.1m of drop, with these details forwarded to the list author.  Its subsequent inclusion (see below) was noted during proof reading of the updated list and Michael Dewey was then informed of its inadvertent inclusion.  This hill was then surveyed by Myrddyn Phillips on the 18^th July 2016 using a Trimble GeoXH 6000 GNSS receiver, resulting in a 503.6m summit height and a 476.2m bwlch height, with these values giving this hill 27.3m of drop.  Welsh Dewey total decreases by one and confirmed as 239.

Foel Cynfal    545.5m at SH 74998 39546 (Deleted from list:  7^th August 2000)

Foel Cynfal (SH 749 395)

This was the second hill that Michael Dewey deleted from his listing of the The 500-Metre Tops of England and Wales.  Its deletion was confirmed in a letter received from the author dated 7^th August 2000.  The hill was inadvertently included in this list by Michael Dewey as it had been surveyed by Myrddyn Phillips on the 15^th July 2000 using a basic levelling technique as having 93½ft / 28.5m of drop, with these details forwarded to the list author.  Its subsequent inclusion (see below) was noted during proof reading of the updated list and Michael Dewey was then informed of its inadvertent inclusion.  This hill was then surveyed by Myrddyn Phillips and Aled Williams on the 1^st July 2017 using a Trimble GeoXH 6000 GNSS receiver, resulting in a 545.5m summit height and a 517.4m bwlch height, with these values giving this hill 28.1m of drop.  Welsh Dewey total decreases by one and confirmed as 240.

Moel y Gyrafolen    536.8m at SH 67218 35292 (Added to list:  23^rd July 2000) 

Moel y Gyrafolen (SH 672 352)

This is the ninth hill added to Michael Dewey’s online website list of the The 500-Metre Tops of England and Wales where only the survey date is given in the accompanying Remarks column, therefore this is used as that for the inclusion date.  This hill was not included in the Mountain tables book published by Constable in 1995, 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.  These details were noted by Myrddyn Phillips who then conducted a basic levelling survey of this hill on the 23^rd 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.  The hill was later surveyed by John Barnard, Graham Jackson and Myrddyn Phillips on the 22^nd February 2013 using a Leica GS15 GNSS receiver, resulting 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.  Welsh Dewey total increases by one and confirmed as 241.

Clip    595.3m at SH 65460 32942 (Added to list:  23^rd July 2000) 

Clip (SH 654 329)

This is the eighth hill added to Michael Dewey’s online website list of the The 500-Metre Tops of England and Wales where only the survey date is given in the accompanying Remarks column, therefore this is used as that for the inclusion date.  This hill was not included in the Mountain tables book published by Constable in 1995, 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.  These details were noted by Myrddyn Phillips who then conducted a basic levelling survey of this hill on the 23^rd 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.  The hill was later surveyed by Myrddyn Phillips and Aled Williams on the 17^th November 2018 using a Trimble GeoXH 6000 GNSS receiver, resulting in a 595.3m summit height and a 564.0m bwlch height, with these values giving this hill 31.3m of drop.  Welsh Dewey total increases by one and confirmed as 240.

Cripiau South Top    525.6m at SN 80202 82864 (Added to list:  22^nd July 2000) 

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

This is the seventh hill added to Michael Dewey’s online website list of the The 500-Metre Tops of England and Wales where only the survey date is given in the accompanying Remarks column, therefore this is used as that for the inclusion date.  This hill was not included in the Mountain tables book published by Constable in 1995, 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.  These details were noted by Myrddyn Phillips who then conducted a basic levelling survey of this hill on the 22^nd July 2000, resulting in 100ft / 30.5m of drop.  These details were forwarded to the list author; Michael Dewey who then included it in his list.  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 took place on the 19^th 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 hill was later surveyed by Myrddyn Phillips on the 10^th April 2019 using a Trimble GeoXH 6000 GNSS receiver, resulting in a 525.6m summit height and a 495.0m bwlch height, with these values giving this hill 30.6m of drop.  Welsh Dewey total increases by one and confirmed as 239.

Foel Cynfal    545.5m at SH 74998 39546 (Added to list:  15^th July 2000)

THIS HILL HAS SUBSEQUENTLY BEEN DELETED FROM THE DEWEY LIST 

Foel Cynfal (SH 749 395)

This is the sixth hill added to Michael Dewey’s online website list of the The 500-Metre Tops of England and Wales where only the survey date is given in the accompanying Remarks column, therefore this is used as that for the inclusion date.  This hill was not included in the Mountain tables book published by Constable in 1995, but 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.  These details were noted by Myrddyn Phillips who then conducted a basic levelling survey of this hill on the 15^th 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 noted during proof reading when an updated copy of the list was received by Myrddyn Phillips.  This hill has subsequently been deleted from the Dewey list (see above).  This hill was then surveyed by Myrddyn Phillips and Aled Williams on the 1^st July 2017 using a Trimble GeoXH 6000 GNSS receiver, resulting in a 545.5m summit height and a 517.4m bwlch height, with these values giving this hill 28.1m of drop.  Welsh Dewey total increases by one and confirmed as 238.

Esgair y Maesnant    503.6m at SN 83220 86275 (Added to list:  11^th July 2000)

THIS HILL HAS SUBSEQUENTLY BEEN DELETED FROM THE DEWEY LIST 

The Trimble GeoXH 6000 set-up position at the summit of Esgair y Maesnant (SN 832 862)

This is the fifth hill added to Michael Dewey’s online website list of the The 500-Metre Tops of England and Wales where only the survey date is given in the accompanying Remarks column, therefore this is used as that for the inclusion date.  This hill was not included in the Mountain tables book published by Constable in 1995, 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.  These details were noted by Myrddyn Phillips who then conducted a basic levelling survey of this hill on the 11^th 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 noted during proof reading when an updated copy of the list was received by Myrddyn Phillips.  This hill has subsequently been deleted from the Dewey list (see above).  This hill was then surveyed by Myrddyn Phillips on the 18^th July 2016 using a Trimble GeoXH 6000 GNSS receiver, resulting in a 503.6m summit height and a 476.2m bwlch height, with these values giving this hill 27.3m of drop.  Welsh Dewey total increases by one and confirmed as 237.

Esgair Greolen    501.4m at SN 83574 92022 (Added to list:  11^th July 2000) 

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

This is the fourth hill added to Michael Dewey’s online website list of the The 500-Metre Tops of England and Wales where only the survey date is given in the accompanying Remarks column, therefore this is used as that for the inclusion date.  This hill was not included in the Mountain tables book published by Constable in 1995, 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.  These details were noted by Myrddyn Phillips who then conducted a basic levelling survey of this hill on the 11^th 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 who then included it in his list.  The hill was later surveyed by Myrddyn Phillips on the 5^th and 13^th May 2016 using a Trimble GeoXH 6000 GNSS receiver, 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.  Welsh Dewey total increases by one and confirmed as 236.

Esgair y Maesnant S.E. Top    505.6m at SN 84268 85679 (Added to list:  11^th July 2000) 

The hill listed as Esgair y Maesnant S.E. Top in the Dewey list (SN 842 856)

This is the third hill added to Michael Dewey’s online website list of the The 500-Metre Tops of England and Wales where only the survey date is given in the accompanying Remarks column, therefore this is used as that for the inclusion date.  This hill was not included in the Mountain tables book published by Constable in 1995, 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.  These details were noted by Myrddyn Phillips who then conducted a basic levelling survey of this hill on the 11^th July 2000, resulting in 100½ft / 30.6m of drop.  These details were forwarded to the list author; Michael Dewey who then included it in his list.  The hill was later surveyed by Myrddyn Phillips on the 18^th July 2016 using a Trimble GeoXH 6000 GNSS receiver, resulting in a 505.6m summit height and a 472.4m bwlch height.  The details for this hill were subsequently analysed via LIDAR initially by Aled Williams and then 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, with these values giving 33.0m of drop and confirming its Dewey status.  Welsh Dewey total increases by one and confirmed as 235.

Lledwyn Mawr    526.1m at SH 90498 28742 (Added to list:  7^th July 2000) 

Lledwyn Mawr (SH 904 287)

This is the second hill added to Michael Dewey’s online website list of the The 500-Metre Tops of England and Wales where only the survey date is given in the accompanying Remarks column, therefore this is used as that for the inclusion date.  This hill was not included in the Mountain tables book published by Constable in 1995, 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 of this hill was estimated sufficient for it to be a potential new Dewey.  These details were noted by David Purchase and Myrddyn Phillips who worked independently but also exchanged all data.  The hill was subsequently surveyed by Myrddyn Phillips on the 7^th July 2000 using a basic levelling technique, resulting in 99½ft / 30.3m of drop.  These details were forwarded to the list author; Michael Dewey who then included it in his list.  This hill was later surveyed on the 2^nd and the 8^th February 2012 by John Barnard, Graham Jackson and Myrddyn Phillips, using a Leica 530 GNSS receiver, resulting in a 526.1m summit height and a 495.1m bwlch height, with these values giving this hill 30.9m of drop, confirming its Dewey status.  Welsh Dewey total increases by one and confirmed as 234.

Foel y Geifr    515m at SH 71636 05099 (Added to list:  26^th June 2000)

THIS HILL HAS SUBSEQUENTLY BEEN DELETED FROM THE DEWEY LIST  

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

This is the first hill added to Michael Dewey’s online website list of the The 500-Metre Tops of England and Wales where only the survey date is given in the accompanying Remarks column, therefore this is used as that for the inclusion date.  This hill was not included in the Mountain tables book published by Constable in 1995, 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 of this hill was estimated sufficient for it to be a potential new Dewey.  These details were noted by Myrddyn Phillips who then conducted a basic levelling survey of this hill on the 26^th June 2000, resulting in 104½ft / 31.9m of drop.  These details were forwarded to the list author; Michael Dewey and the hill was then included in his list.  Welsh Dewey total increases by one and confirmed as 233.

Foel Ystrodur Fawr    518m at SH 81446 34040 (Added to list:  25^th May 2000) 

This was one of three hills (all in Wales) added on the 25^th May 2000 to Michael Dewey’s online website list of the The 500-Metre Tops of England and Wales.  This hill was not included in the Mountain tables book published by Constable in 1995, 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 of this hill was estimated sufficient for it to be a potential new Dewey.  These details were noted by Myrddyn Phillips who then conducted a basic levelling survey of this hill on the 4^th May 2000, resulting in 107ft / 32.6m of drop.  These details were forwarded to the list author; Michael Dewey and the hill was then included in his list.  Welsh Dewey total increases by one and confirmed as 232.

Y Blaen Llym    554m at SH 68530 46413 (Added to list:  25^th May 2000) 

The ridge leading from Y Blaen Llym on the right toward Allt Fawr on the left

This hill was one of three additions made on the 25^th May 2000 to Michael Dewey’s online website list of the The 500-Metre Tops of England and Wales.  This hill was not included in the Mountain tables book published by Constable in 1995, 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 of this hill was estimated sufficient for it to be a potential new Dewey.  These details were noted by Myrddyn Phillips who then conducted a basic levelling survey of this hill on the 5^th May 2000, resulting in 100ft / 30.5m of drop.  These details were forwarded to the list author; Michael Dewey and the hill was then included in his list.  Its listed name of Y Blaen Llym is a partly invented and transposed name suggested as being appropriate for this hill by Paddy Buckley after an enquiry from Rob Woodall, with the name based on the near crag of Carreg Flaenllym which appears on contemporary Ordnance Survey 1:25,000 Explorer maps.  This hill was subsequently line surveyed using a level and staff by John Barnard and Myrddyn Phillips on the 16^th March 2010, resulting in 30.6m of drop, and therefore confirming its Dewey status.  Welsh Dewey total increases by one and confirmed as 231.

Pen Ochr y Bwlch    564.3m at SH 80957 17269 (Added to list:  25^th May 2000) 

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

This was one of three hills added on the 25^th May 2000 to Michael Dewey’s online website list of the The 500-Metre Tops of England and Wales.  This hill was not included in the Mountain tables book published by Constable in 1995, 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 of this hill was estimated sufficient for it to be a potential new Dewey.  These details were noted by Myrddyn Phillips who then conducted a basic levelling survey of this hill on the 28^th April 2000, resulting in 115ft / 35.1m of drop.  These details were forwarded to the list author; Michael Dewey and the hill was then included in his list.  Its listed name of Pen Ochr y Bwlch is a partly invented and transposed name with Myrddyn Phillips suggesting the transposed part; Ochr y Bwlch, and Paddy Buckley suggesting the addition invented part; Pen, with this name based on the hill’s proximity to Ochr y Bwlch, which is a prominent name that appears on contemporary Ordnance Survey maps.  This hill was subsequently surveyed by Myrddyn Phillips on the 8^th March 2014 using a Trimble GeoXH 6000 GNSS receiver, 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.  Welsh Dewey total increases by one and confirmed as 230.

Foel Uchaf    565m at SN 80274 91203 (Deleted from list:  11^th May 2000) 

THIS HILL HAS SUBSEQUENTLY BEEN REINSTATED TO THE DEWEY LIST 

This was the first hill that Michael Dewey deleted from his listing of the The 500-Metre Tops of England and Wales.  The date this hill was removed from the list is unknown, however its deletion probably coincided with the inclusion of Carn Hyddgen (SN 792 908) (see below) to the list, as this latter hill is given as 566m in height whilst Foel Uchaf is given as 565m in height on contemporary Ordnance Survey maps.  The premise being that the higher hill superseded the lower, and therefore the lower hill was removed.  However, Foel Uchaf was subsequently reinstated to the Dewey list as its interpolated bwlch height coupled with its 565m summit spot height gives the hill sufficient drop to be listed as a Dewey (see above).  Welsh Dewey total decreases by one and confirmed as 229.

Carn Hyddgen    566m at SN 79233 90831 (Added to list:  11^th May 2000) 

This hill was one of two additions on the 11^th May 2000 to the The 500-Metre Tops of England and Wales list hosted on Michael Dewey’s website.  This hill was not included in the Mountain tables book published by Constable in 1995, but with a 566m summit spot height and bwlch contouring between 510m – 520m that appear on the Ordnance Survey 1:25,000 Explorer map, it was an automatic entry to this hill.  However, its proximity to the 565m map heighted hill named Foel Uchaf (SN 802 912) on contemporary Ordnance Survey maps, 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.  These details were noted by David Purchase and Myrddyn Phillips who worked independently but also exchanged all data and once forwarded to the list author; Michael Dewey, it was included in his list.  The bwlch height was revised to 514m when the Ordnance Survey Vector Map Local became available online and which was hosted on the Geograph website and entitled the Interactive Coverage Map.  Welsh Dewey total increases by one and confirmed as 230.

Stanky Hill    506.7m at SO 16390 76419 (Added to list:  8^th May 2000) 

Graham Jackson operating the level at the bwlch of Stanky Hill

This hill was one of four (all in Wales) additions made on the 8^th May 2000 to the The 500-Metre Tops of England and Wales list hosted on Michael Dewey’s website.  This hill was not included in the Mountain tables book published by Constable in 1995, 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.  These details were noted by David Purchase and Myrddyn Phillips who worked independently but also exchanged all data.  The hill was subsequently surveyed by Myrddyn Phillips on the 30^th April 2000 using a basic levelling technique, resulting in 103ft / 31.4m of drop.  These details were forwarded to the list author; Michael Dewey who then included it in his list.  This hill was later surveyed on the 16^th February 2012 by John Barnard, Graham Jackson and Myrddyn Phillips with assistance from Aled Williams, using a Leica 530 GNSS receiver and a level and staff, resulting in a 506.7m summit height and a 476.4m bwlch height, with these values giving this hill 30.3m of drop, confirming its Dewey status.  Welsh Dewey total increases by one and confirmed as 229.

Mynydd Cwmeiddew    507m at SH 75101 10600 (Added to list:  8^th May 2000) 

This was one of four hills added on the 8^th May 2000 to the The 500-Metre Tops of England and Wales list hosted on Michael Dewey’s website.  This hill was not included in the Mountain tables book published by Constable in 1995, but with a 507m summit spot height and bwlch contouring between 470m – 480m that appear on the Ordnance Survey 1:25,000 Explorer map, it was judged from interpolation to have sufficient drop to enter the list.  These details were noted by David Purchase and once forwarded to the list author; Michael Dewey, it was included in his list.  The bwlch height was revised to 473m when the Ordnance Survey Vector Map Local became available online and which was hosted on the Geograph website and entitled the Interactive Coverage Map.  Welsh Dewey total increases by one and confirmed as 228.

Mynydd Tynewydd    517.8m at SN 93790 00902 (Added to list:  8^th May 2000) 

The Trimble GeoXH 6000 gathering data at the summit of Mynydd Tynewydd (SN 937 009)

This hill was one of four additions made on the 8^th May 2000 to the The 500-Metre Tops of England and Wales list hosted on Michael Dewey’s website.  With its listed name being prominent along with that of Mynydd Ystradffernol on contemporary Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer maps.  This hill was not included in the Mountain tables book published by Constable in 1995, but with a 518m summit spot height and bwlch contouring between 480m – 490m that appear on the Ordnance Survey 1:25,000 Explorer map, it was judged from interpolation to have sufficient drop to enter the list.  These details were noted by David Purchase and once forwarded to the list author; Michael Dewey, it was included in his list.  This hill was subsequently surveyed on the 25^th August 2018 by Myrddyn Phillips and Aled Williams with assistance from Mark Trengove, using a Trimble GeoXH 6000 GNSS receiver, resulting in a 517.8m summit height and a 484.9m bwlch height, with these values giving this hill 32.9m of drop, which confirmed its Dewey status.  Welsh Dewey total increases by one and confirmed as 227.

Carreg Cadno    538.4m at SN 87423 16132 (Added to list:  8^th May 2000) 

Carreg Cadno (SN 874 161)

This hill was one of four additions made to the The 500-Metre Tops of England and Wales, with the details added to the list on the 8^th May 2000 and which was hosted on Michael Dewey’s website.  This hill was not included in the Mountain tables book published by Constable in 1995, but with a 538m summit spot height and bwlch contouring between 500m – 510m that appears on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer maps, the interpolated bwlch height was sufficient for the hill to be considered for Dewey status.  These details were noted by Myrddyn Phillips and Rob Woodall, with the latter then conducting an on-site survey of the bwlch, resulting in an estimated drop for the hill of 32m – 33m, these details were forwarded to the list author; Michael Dewey and the hill was added to his list.  The height and position of this hill’s summit and bwlch were subsequently ascertained from LIDAR analysis conducted by Aled Williams which confirmed its Dewey status, and the hill was then surveyed on the 7^th July 2019 by Myrddyn Phillips and Aled Williams, with assistance from Mark Trengove, using a Trimble GeoXH 6000 GNSS receiver, resulting in a 538.4m summit height and a 502.9m bwlch height, with these values giving this hill 35.5m of drop.  Welsh Dewey total increases by one and confirmed as 226.

Moel Cae-howel    508m at SH 97832 33087 (Added to list:  3^rd May 2000) 

Moel Cae-howel (SH 978 330)

This hill was one of sixteen (thirteen in Wales and three in England) added to Michael Dewey’s online list of the The 500-Metre Tops of England and Wales on the 3^rd May 2000.  This hill was not included in the Mountain tables book published by Constable in 1995, 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 sufficient drop according to contemporary Ordnance Survey maps to be an automatic entry to the Dewey list.  These details were noted by Myrddyn Phillips and once forwarded to the list author; Michael Dewey, it was included in his list.  Welsh Dewey total increases by one and confirmed as 225.

Foel Boeth    509m at SH 80481 47800 (Added to list:  3^rd May 2000) 

This was one of sixteen hills added on the 3^rd May 2000 to Michael Dewey’s online website list of the The 500-Metre Tops of England and Wales.  This hill was not included in the Mountain tables book published by Constable in 1995, 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 sufficient drop to have been included as an automatic entry to the Dewey list.  These details were noted by David Purchase and Myrddyn Phillips who worked independently but also exchanged all data and these details were forwarded to the list author; Michael Dewey.  Welsh Dewey total increases by one and confirmed as 224.

Moel y Llyn East Top    511m at SN 71753 91288 (Added to list:  3^rd May 2000) 

This was one of sixteen hills added on the 3^rd May 2000 to Michael Dewey’s online website list of the The 500-Metre Tops of England and Wales.  This hill was not included in the Mountain tables book published by Constable in 1995, 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 was an automatic entry to the Dewey list.  These details were noted by Myrddyn Phillips and once forwarded to the list author; Michael Dewey, it was included in his list.  Its listed name of Moel y Llyn East Top is an invented and directional name based on this hill’s proximity to the adjacent and higher Moel y Llyn (SN 712 916), although topographically it is adjoined to Banc Bwlch y Garreg (SN 729 918).  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.  Welsh Dewey total increases by one and confirmed as 223.

Pen Dihewyd    513m at SN 77882 79702 (Added to list:  3^rd May 2000) 

Pen Dihewyd (SN 778 797)

This hill was one of sixteen additions made to the The 500-Metre Tops of England and Wales, with the details added to the list on the 3^rd May 200o and which was hosted on Michael Dewey’s website.  This hill was not included in the Mountain tables book published by Constable in 1995, but with a 513m summit spot height and bwlch contouring between 470m – 480m on the Ordnance Survey 1:25,000 Explorer map, this hill has a minimum 30m of drop according to contemporary Ordnance Survey maps and therefore was an automatic entry to the Dewey list.  These details were noted by Myrddyn Phillips and once forwarded to the list author; Michael Dewey, it was included in his list.  Welsh Dewey total increases by one and confirmed as 222.

Craig Fawr    517.9m at SN 87939 63846 (Added to list:  3^rd May 2000) 

The Trimble GeoXH 6000 gathering data at the summit of Craig Fawr (SN 879 638)

This was one of sixteen hills added on the 3^rd May 2000 to Michael Dewey’s online website list of the The 500-Metre Tops of England and Wales.  This hill was not included in the Mountain tables book published by Constable in 1995, but with a 519m summit spot height and a 477m bwlch spot height that appear on the Ordnance Survey 1:25,000 Explorer map, this hill has 42m of drop according to contemporary Ordnance Survey maps and therefore was an automatic entry to the Dewey list.  These details were noted by David Purchase and Myrddyn Phillips who worked independently but also exchanged all data and these details were forwarded to the list author; Michael Dewey.  This hill was subsequently surveyed on the 27^th February 2019 by Myrddyn Phillips using a Trimble GeoXH 6000 GNSS receiver, 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.  Welsh Dewey total increases by one and confirmed as 221.

Priddellau    534m at SN 85454 67796 (Added to list:  3^rd May 2000) 

At the summit of Priddellau (SN 854 677)

This hill was another added to Michael Dewey’s list of the The 500-Metre Tops of England and Wales and formed one of sixteen additions added to this list on the 3^rd May 2000.  This hill was not included in the Mountain tables book published by Constable in 1995, 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 according to contemporary Ordnance Survey maps had 30m of drop and was an automatic entry to the list.  These details were noted by David Purchase and Myrddyn Phillips who worked independently but also exchanged all data and these details were forwarded to the list author; Michael Dewey.  Reports from subsequent visits to the summit indicated that higher ground existed toward the north-east from where the 533m spot height appears on the ground, and latterly this position has been given a 534m spot height on the WalkLakes website which hosts an interactive map originated from the Ordnance Survey Open Data programme.  Welsh Dewey total increases by one and confirmed as 220.

Llechwedd Llwyd    535m at SH 83868 81410 (Added to list:  3^rd May 2000)

THIS HILL HAS SUBSEQUENTLY BEEN DELETED FROM THE DEWEY LIST 

This hill was one of sixteen additions to the The 500-Metre Tops of England and Wales and which appeared on the 3^rd May 2000 on Michael Dewey’s list hosted on his website.  This hill was not included in the Mountain tables book published by Constable in 1995, but with a 535m summit spot height and bwlch contours between 500m – 510m on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map this hill was judged from contour interpolation to have sufficient drop to be included in the Dewey list.  These details were noted by Myrddyn Phillips and once forwarded to the list author, it was included in the list.  This hill has subsequently been deleted from the Dewey list (see above).  Welsh Dewey total increases by one and confirmed as 219.

Bryn-llus    547.8m at SJ 08564 40894 (Added to list:  3^rd May 2000) 

Gathering data with the Leica 530 at the summit of Bryn-llus (SJ 085 408)

Bryn-llus was one of sixteen hills added to the The 500-Metre Tops of England and Wales on the 3^rd May 2000, and which appeared in the list hosted on Michael Dewey’s website.  This hill was not included in the Mountain tables book published by Constable in 1995, 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 30m of drop according to contemporary Ordnance Survey maps and therefore was an automatic entry to the Dewey list.  These details were noted by Myrddyn Phillips and once forwarded to the list author; Michael Dewey, it was included in his list.  This hill was later surveyed on the 26^th January 2010 by John Barnard, Graham Jackson and Myrddyn Phillips using a Leica 530 GNSS receiver, resulting in a 547.8m summit height and a 516.1m bwlch height, with these values giving this hill 31.7m of drop, confirming its Dewey status.  Welsh Dewey total increases by one and confirmed as 218.

Craig Llyn Du    c 553m at SH 65552 29569 (Added to list:  3^rd May 2000) 

Craig Llyn Du (SH 655 295)

This was one of sixteen hills added on the 3^rd May 2000 to Michael Dewey’s online website list of the The 500-Metre Tops of England and Wales.  This hill was not included in the Mountain tables book published by Constable in 1995, but with a small uppermost 550m summit ring contour and bwlch contouring between 510m – 520m on the Ordnance Survey 1:25,000 Explorer map this hill was an automatic entry to the Dewey list.  These details were noted by Myrddyn Phillips and once forwarded to the list author; Michael Dewey, it was included in his list.  Its listed name of Craig Llyn Du was suggested by Rob Woodall and is invented, and based on its rocky profile and its proximity to Llyn Du.  Welsh Dewey total increases by one and confirmed as 217.

Orddu    553.8m at SH 96338 42337 (Added to list:  3^rd May 2000) 

Orddu (SH 963 423)

This hill was one of sixteen additions made to the The 500-Metre Tops of England and Wales list on the 3^rd May 2000, with the details added to the list which was hosted on Michael Dewey’s website.  This hill was not included in the Mountain tables book published by Constable in 1995, but with a 555m summit spot height and bwlch contouring between 520m – 530m appearing 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.  These details were noted by David Purchase and Myrddyn Phillips who worked independently but also exchanged all data.  By this stage Myrddyn Phillips had conducted two basic levelling surveys of this hill on the 29^th March 2000 and the 16th April 2000, with the average of these two surveys giving 112½ft / 34.3m of drop.  These details were forwarded to the list author; Michael Dewey who then included it in his list.  This hill was subsequently surveyed on the 19^th January 2020 by Myrddyn Phillips and Aled Williams, using a Trimble GeoXH 6000 GNSS receiver, resulting in a 553.8m summit height and a 520.5m bwlch height, with these values giving this hill 33.3m of drop, confirming its Dewey status.  Welsh Dewey total increases by one and confirmed as 216.

Iwerddon    583m at SH 68822 48217 (Added to list:  3^rd May 2000)

THIS HILL HAS SUBSEQUENTLY BEEN DELETED FROM THE DEWEY LIST 

Iwerddon (SH 688 482) during the level and staff line survey that deleted this hill from Dewey status

This hill was one of sixteen additions to the The 500-Metre Tops of England and Wales and which appeared on the 3^rd May 2000 on Michael Dewey’s website list.  This hill was not included in the Mountain tables book published by Constable in 1995, but with a 583m summit spot height and bwlch contours between 550m – 560m on the Ordnance Survey 1:25,000 Explorer map this hill was judged from contour interpolation to have sufficient drop to be included in the Dewey list.  These details were noted by David Purchase and Myrddyn Phillips who worked independently but also exchanged all data and these details were forwarded to the list author; Michael Dewey.  Subsequently Myrddyn Phillips conducted a basic levelling survey of this hill on the 5^th May 2000 without prior knowledge of its recent inclusion, resulting in the hill considered to have just over 30m of drop.  This hill has subsequently been deleted from the Dewey list (see above).  Welsh Dewey total increases by one and confirmed as 215.

Foel-fras    586m at SH 72803 48165 (Added to list:  3^rd May 2000) 

Foel-fras (SH 728 481)

Foel-fras was one of sixteen hills that were added to the list of the The 500-Metre Tops of England and Wales on the 3^rd May 2000 and which appeared on Michael Dewey’s website.  This hill was not included in the Mountain tables book published by Constable in 1995, but with a 586m summit spot height and bwlch contours between 550m – 560m on the Ordnance Survey 1:25,000 Explorer map this hill was judged from contour interpolation to have sufficient drop to be included in the Dewey list.  These details were noted by David Purchase and Myrddyn Phillips who worked independently but also exchanged all data and these details were forwarded to the list author; Michael Dewey.  Subsequently Myrddyn Phillips conducted a basic levelling survey of this hill on the 4^th May 2000 without prior knowledge of its recent inclusion, resulting in the hill having over 30m of drop.  Welsh Dewey total increases by one and confirmed as 214.

Craig y Moch (Craig Fach)    608.8m at SH 63495 55248 (Added to list:  3^rd May 2000) 

Craig y Moch (Craig Fach) (SH 634 552)

This hill was one of sixteen additions on the 3^rd May 2000 to Michael Dewey’s list of the The 500-Metre Tops of England and Wales, and which was added to the list hosted on his website.  This hill was not included in the Mountain tables book published by Constable in 1995, but with a 609m summit spot height and a 569m bwlch spot height that appear on the Ordnance Survey 1:25,000 Explorer map this hill was an automatic entry to the Dewey list.  These details were noted by David Purchase and Myrddyn Phillips who worked independently but also exchanged all data and these details were forwarded to the list author; Michael Dewey, with David having assessed the hill’s qualification on site.  Its listed name of Craig y Moch is invented and partly transposed from the bwlch name to the west of this hill’s summit, with the use of the bracketed Craig Fach being a later addition.  This hill was subsequently surveyed by James Whitworth of Leica Geosystems using a Leica SmartRover 1200 on the 11^th August 2008 in conjunction with the fledgling team of G&J Surveys; consisting of John Barnard, Graham Jackson and Myrddyn Phillips, resulting in a 608.8m summit height and this hill’s retention as a Dewey.  Welsh Dewey total increases by one and confirmed as 213.

Bryniau Gleision    538.1m at SO 08449 16121 (Added to list:  1^st May 2000) 

Bryniau Gleision (SO 084 161)

This is was one of seven (three in Wales and four in England) hills added to the listing of the The 500-Metre Tops of England and Wales on the 1^st May 2000 and included in Michael Dewey’s list hosted on his website, the addition of all seven hills are credited to David Purchase.  This hill was not included in the Mountain tables book published by Constable in 1995, 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, it was judged from interpolation to have sufficient drop to enter the list.  Having been analysed via LIDAR by Aled Williams, Bryniau Gleision was subsequently surveyed my Myrddyn Phillips and Aled Williams on the 19^th April 2019 using a Trimble GeoXH 6000 GNSS receiver, resulting in a 538.1m summit height and a 502.4m bwlch height, with these values giving this hill 35.8m of drop, confirming its Dewey status.  Welsh Dewey total increases by one and confirmed as 212.

Domen Milwyn    555m at SN 80832 71946 (Added to list:  1^st May 2000) 

Domen Milwyn was one of seven hills added to the listing of the The 500-Metre Tops of England and Wales on the 1^st May 2000 and included in Michael Dewey’s list hosted on his website, the addition of all seven hills are credited to David Purchase.  This hill was not included in the Mountain tables book published by Constable in 1995, 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, it was judged from interpolation to have sufficient drop to enter the list.  Welsh Dewey total increases by one and confirmed as 211.

Pen y Lladron    600.9m at SJ 09917 37394 (Added to list:  1^st May 2000) 

This hill was one of seven that were added on the 1^st May 2000 to the The 500-Metre Tops of England and Wales and appeared in the list hosted on Michael Dewey’s website, the addition of all seven hills are credited to David Purchase.  With its listed name being a suggestion on David’s part based on its proximity to the Nant y Lladron; a stream positioned to the north north-west of the summit.  This hill was not included in the Mountain tables book published by Constable in 1995, but with a 604m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and bwlch contouring between 570m – 580m, it was judged from interpolation to have sufficient drop to enter the list.  This hill was subsequently surveyed on the 22^nd October 2013 by Alan Dawson using a Leica RX1250 GNSS receiver, resulting in a 600.9m summit height and a 568.6m bwlch height, with these values giving this hill 32.3m of drop, confirming its Dewey status.  Welsh Dewey total increases by one and confirmed as 210.

Pen y Bwlch Gwyn    501.5m at SH 93291 41184 (Added to list:  Early April 2000) 

Gathering data with the Trimble GeoXH 6000 at the summit of Pen y Bwlch Gwyn (SH 932 411)

This hill was one of six (five in Wales and one in England) that were added to the The 500-Metre Tops of England and Wales and appeared in the list hosted on Michael Dewey’s website, and which formed the first batch of additions to this list.  The exact date of inclusion is unknown; however these six additions were found by Rob Woodall and reported in a letter dated the 12^th April 2000, with this hill’s inclusion likely to be early April 2000.  This hill was not included in the Mountain tables book published by Constable in 1995, but with a 502m summit spot height and a 468m bwlch spot height that appear on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer maps this hill was an automatic entry to the Dewey list.  Pen y Bwlch Gwyn was subsequently surveyed my Myrddyn Phillips and Aled Williams on the 10^th October 2015 using a Trimble GeoXH 6000 GNSS receiver, resulting in a 501.5m summit height and a 467.5m bwlch height, with these values giving this hill 34.0m of drop.  Welsh Dewey total increases by one and confirmed as 209.

Mynydd Rhyd-galed    502.4m at SH 69906 04331 (Added to list:  Early April 2000) 

LIDAR image of Mynydd Rhyd-galed (SH 699 043)

This is one of six hill’s that were added to Michael Dewey’s list of The 500-Metre Tops of England and Wales and appeared on his website, and which formed the first batch of additions to this list.  The exact date of inclusion is unknown; however these six additions were found by Rob Woodall and reported in a letter dated the 12^th April 2000, with this hill’s inclusion likely to be early April 2000.  When Constable published the Mountain tables book in 1995, this hill was not included, but with a small uppermost 500m ring contour and bwlch contouring between 440m – 450m on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map, according to contemporary map detail it was an automatic entry to the Dewey list.  The summit and bwlch heights were revised to 502m and 442m respectively when the Ordnance Survey Vector Map Local hosted on the Geograph website and entitled the Interactive Coverage Map became available online.  Subsequent LIDAR analysis conducted by Myrddyn Phillips confirmed its status with a 502.4m summit height and a 442.7m bwlch height, with these values giving this hill 59.7m of drop.  Welsh Dewey total increases by one and confirmed as 208.

Twr Pen-cyrn    529m at SO 20285 14498 (Added to list:  Early April 2000)  

THIS HILL HAS SUBSEQUENTLY BEEN DELETED FROM THE DEWEY LIST 

This hill was one of six that were added to the The 500-Metre Tops of England and Wales and appeared in the list hosted on Michael Dewey’s website, and which formed the first batch of additions to this list.  The exact date of inclusion is unknown; however these six additions were found by Rob Woodall and reported in a letter dated the 12^th April 2000, with this hill’s inclusion likely to be early April 2000.  This hill was not included in the Mountain tables book published by Constable in 1995, but with a 529m summit spot height adjoined to a triangulation pillar that appears on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map and bwlch contouring between 490m – 500m, it was judged from interpolation to have sufficient drop to enter the list.  Welsh Dewey total increases by one and confirmed as 207.

Craig Rhiwarth    532m at SJ 05486 27121 (Added to list:  Early April 2000) 

Craig Rhiwarth (SJ 054 271)

This is one of six hills that formed the first additions to the The 500-Metre Tops of England and Wales and was added by Michael Dewey and appeared in the list hosted on his website.  The exact date of inclusion is unknown; however these six additions were found by Rob Woodall and reported in a letter dated the 12^th April 2000, with this hill’s inclusion likely to be early April 2000.  This hill was not included in the 1995 Mountain tables book published by Constable, but with a 532m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and bwlch contouring between 460m – 470m, according to contemporary map detail it was an automatic entry to the Dewey list.  Welsh Dewey total increases by one and confirmed as 206.

Foel Boeth    541m at SH 83456 33791 (Added to list:  Early April 2000)  

This hill was one of six that formed the first additions to the The 500-Metre Tops of England and Wales and was added to the list which appeared on Michael Dewey’s website.  The exact date of inclusion is unknown; however these six additions were found by Rob Woodall and reported in a letter dated the 12^th April 2000, with this hill’s inclusion likely to be early April 2000.  This hill was not included in the 1995 Constable publication, but with a 541m summit spot height that appears on the Ordnance Survey 1:25,000 Outdoor Leisure (latterly Explorer) map and bwlch contouring between 490m – 500m, according to contemporary map detail it was an automatic entry to the Dewey list.  Welsh Dewey total increases by one and confirmed as 205.

1995 – Constable publishes Mountain tables with The 500-Metre Tops of England and Wales. 

Welsh Dewey total confirmed as 204.