Mapping Mountains – Hill Reclassifications – Humps

Moel Maenefa (SJ 087 744) – proposed Subhump reinstated to Hump

This is the fourty first in a series of Hill Reclassification posts that detail hills whose status has either been altered in the listing of the Humps (HUndred Metre Prominences) through map study, surveys or LIDAR analysis that I have been involved in, or it is the recommendation that their status is altered.

LIDAR image of Moel Maenefa (SJ 087 744)

Many preceding posts detailing these hill reclassifications are retrospective as they were initiated from studying the Ordnance Survey Vector Map Local hosted on the Geograph website and which was entitled the Interactive Coverage Map, or from surveying with the Trimble GeoXH 6000, or from LIDAR analysis, and for this proposed reinstatement that affects the Humps the email I posted on the pedantic@groups.io forum in relation to this hill was dated 09.01.25.

The listing of Humps was published in book format by Lulu in 2009 and entitled More Relative Hills of Britain, its author; Mark Jackson gives credit to a number of people who contributed toward the formation of this list, these include; Eric Yeaman, Alan Dawson, Clem Clements, Rob Woodall, Bernie Hughes, Pete Ridges and others.  When the list was published in book format there were 2987 Humps listed with their criteria being any British hill that has 100m or more of drop, irrespective of their height.  Accompanying the main list is a sub category entitled Subhumps, with the criteria being any British hill that has 90m or more and below 100m of drop.

More Relative Hills of Britain by Mark Jackson

The details for this proposed reinstatement appear below:

The name the hill is listed by is Moel Maenefa, and it is adjoined to the Moel y Gamelin group of hills, which are situated in the north-eastern part of Wales, and it is positioned with minor roads to its north, north-west and east, with the A55 road farther to its north and the B5429 road farther to its west, and has the small community of Rhuallt towards the north-west. 

Summit extract from the Ordnance Survey 1:25,000 Explorer map

When the list was first published this hill was classified as a Hump with 100m of drop, based on the 290m summit height adjoined to an old trig pillar and which appeared on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer maps of the day, and a 190m bwlch height, which upon first compilation was probably based on interpolation of 10m contouring.  The triangulation pillar stood on a plinth and this has now been removed from the summit, with the contemporary online Ordnance Survey 1:25,000 Explorer map giving an erroneous 286m summit height.

Bwlch extract from the Ordnance Survey 1:25,000 Explorer map

This hill was subsequently reclassified to Subhump status in January 2013 and listed with 98m of drop, based on the natural col being on the old minor road south of the A55 road cutting, which was supported by old maps.  This was also supported by a 191m spot height appearing on this minor road on the Ordnance Survey Vector Map Local hosted on the Geograph website and which was entitled the Interactive Coverage Map.

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.

In 2023 the team in charge of the listing of Humps first analysed this hill with LIDAR and it remained classified as a Subhump with 98.8m of drop, based on a 289.5m summit height and a 190.7m bwlch height, with a note stating; Natural col extant.

The hill was subsequently analysed using LIDAR by Myrddyn Phillips and his findings posted on the pedantic forum, this post appears below:   

 

I haven’t posted one of these in quite some time, so if not interested in numerical detail or Humps I’d suggest you skip this post.

Many years ago the status of Moel Maenefa (SJ 087 744) was under debate.  It’s currently listed as a Subhump with 98.8m of drop, having once been listed as a Hump.  However, its current status is dependent upon its natural col being intact. 

If prioritising an intact natural col over a cutting, and if the natural col of this hill is no longer intact, the hill would be listed as a Hump with 103.2m of drop due to the A55 road cutting to the north of the summit.

Having driven this road a few days ago in slushy conditions I thought it time to have a look at this hill’s details with LIDAR.  Something I’d been meaning to do for a long time.

A col just south of the A55 road cutting does exist and LIDAR gives this as 190.690m positioned at SJ 08701 75852.  This coupled with the LIDAR summit of 289.470m at SJ 08711 74413, gives its current listed drop of 98.8m.

But does the natural col still exist?

Old Six-Inch maps give a variety of bench mark heights just to the south-west of where LIDAR places the 190.690m col.  These include documented heights of 623.5ft, 626.43ft, 625.1ft and 625.2ft.  These were probably positioned on or near an old building and are periphery in deciding whether the natural col still exists.

Before the A55 road cutting, the area of the col consisted of minor roads forming a diagonal crossroad.  These ran north, south, north-east and south-west.  Three of these roads still exist, with the northerly now swallowed by the cutting.

The 190.690m position at SJ 08701 75852 is placed in the centre of the north-easterly and south-westerly roads as they are intersected by the southerly road.  LIDAR contouring hereabouts is stretched following the course of these minor roads.  This indicates terra-forming and therefore the natural col cannot exist at this point.  On a subjective note; these LIDAR col contours do not look natural, which isn’t surprising as the land hereabouts is terra-formed. 

Now you could argue that this doesn’t really matter as this road col is near enough.

Importantly LIDAR contouring also indicates that the 190.690m col is not where the natural col once lay, as the 191m contour is flattened from SJ 08711 75856 to SJ 08769 75878.  This indicates that prior to the A55 road cutting this contour would have extended and culminated at the old natural col.  The north-easterly road hereabouts has cut into the 191m contour, only slightly, but it still has.  This position is approximately 40 – 45 metres eastward from the SJ 08701 75852 position currently taken as the col for Moel Maenefa.

Conclusion; the natural col no longer exists and therefore this hill should be listed as a Hump with 103.2m of drop.

A LIDAR image is attached.  The thick yellow contour is at 200m.  The blue and green contours are at 1m intervals.  The thick red contours are at 10m intervals.  The thin red and white contours are at 0.1m intervals.  The intersection of one of the thin red contours is where LIDAR places the 190.7m position that is currently taken as the col. 

LIDAR bwlch image of Moel Maenefa

Therefore, the proposed reinstatement of this hill from Subhump to Hump status is due to LIDAR analysis, resulting in a 289.5m summit height and a 186.3m bwlch height, with these values giving this hill 103.2m of drop.

 

The full details for the hill are:

Name:  Moel Maenefa

OS 1:50,000 map:  116

OS 1:25,000 map:  264, 265

Summit Height:  289.5m (LIDAR)

Summit Grid Reference:  SJ 08713 74418 (as listed in the Humps, with LIDAR analysis giving SJ 08711 74413)

Bwlch Height:  190.7m (as listed in the Humps, as the natural bwlch no longer exists, LIDAR analysis gives 186.3m to the A55 road cutting bwlch)

Bwlch Grid Reference:  SJ 0870 7585 (as listed in the Humps, as the natural bwlch no longer exists, LIDAR analysis gives SJ 08948 76019 and SJ 08949 76019 to the A55 road cutting bwlch)

Drop:  98.8m (as listed in the Humps, as the natural bwlch no longer exists, LIDAR analysis gives 103.2m of drop to the A55 road cutting bwlch)

 

Myrddyn Phillips (February 2025)

 

Mapping Mountains – Hill Reclassifications – Humps

Way Stone Edge (SD 999 140) – proposed Subhump deletion

This is the fourtieth in a series of Hill Reclassification posts that detail hills whose status has either been altered in the listing of the Humps (HUndred Metre Prominences) through map study, surveys or LIDAR analysis that I have been involved in, or it is the recommendation that their status is altered.

LIDAR summit image of Way Stone Edge (SD 999 140)

Many preceding posts detailing these hill reclassifications are retrospective as they were initiated from studying the Ordnance Survey Vector Map Local that was hosted on the Geograph website and which was entitled the Interactive Coverage Map, or from surveying with the Trimble GeoXH 6000, or from LIDAR analysis, and for this proposed deletion that affects the Humps the email I posted on the pedantic@groups.io forum in relation to this hill was dated 20.06.23.

The listing of Humps was published in book format by Lulu in 2009 and entitled More Relative Hills of Britain, its author; Mark Jackson gives credit to a number of people who contributed toward the formation of this list, these include; Eric Yeaman, Alan Dawson, Clem Clements, Rob Woodall, Bernie Hughes, Pete Ridges and others.  When the list was published in book format there were 2987 Humps listed with their criteria being any British hill that has 100m or more of drop, irrespective of their height.  Accompanying the main list is a sub category entitled Subhumps, with the criteria being any British hill that has 90m or more and below 100m of drop.

More Relative Hills of Britain by Mark Jackson

The details for this proposed deletion appear below:

The name the hill is listed by is Way Stone Edge, and it is the highest hill in its own group of hills, which are situated in the southern Pennines, and it is positioned with the M62 motorway and the A672 road to its north-west, and the A640 road to its south-east, and has the village of Denshaw towards the south south-west. 

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

This hill is currently listed as a Subhump with 94m of drop based on the 418.6m summit height ascertained from LIDAR analysis and a 388m col height, based on the spot height that appears on the Ordnance Survey 1:25,000 Explorer map.  The proposed deletion of this hill in the listing of the Humps (HUndred Metre Prominences) was instigated by LIDAR analysis conducted by Myrddyn Phillips.

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

The col height of 388m for the listed drop value of 94m is taken to the A62 cutting.  The protocol followed in the listing of the Humps specifies that the height of an extant natural col is favoured over that of the height in the depth of a cutting, even if the latter is lower on the hill to hill traverse.  As LIDAR contouring implies the natural col for this hill is intact, it is this height value that should be taken for the listing of the Humps within the drop of this hill.

LIDAR col image of Way Stone Edge

Therefore, the proposed deletion of this hill from Subhump status is due to LIDAR analysis, resulting in a 481.6m summit height and a 399.6m col height, with these values giving this hill 82.1m of drop.

 

The full details for the hill are:

Name:  Way Stone Edge

OS 1:50,000 map:  109

OS 1:25,000 map:  21

Summit Height:  481.6m (LIDAR)

Summit Grid Reference:  SD 99953 14049 (as listed in the Humps, with LIDAR analysis giving SD 99956 14046)

Col Height:  388m (as listed in the Humps, with LIDAR analysis giving 399.6m to the natural col)

Col Grid Reference:  SE 019 095 (as listed in the Humps, with LIDAR analysis giving SE 02035 09664)

Drop:  94m (as listed in the Humps, with LIDAR analysis giving 82.1m using the natural col)

 

Myrddyn Phillips (July 2023)

 

 

 

 

 

  

Mapping Mountains – Hill Reclassifications – Humps

 

Werfa (SS 912 947) – Subhump deletion

This is the thirty eighth in a series of Hill Reclassification posts that detail hills whose status has either been altered in the listing of the Humps (HUndred Metre Prominences) through map study, surveys or LIDAR analysis that I have been involved in, or it is the recommendation that their status is altered.

Werfa (SS 912 947) 

Many preceding posts detailing these hill reclassifications are retrospective as they were initiated from studying the Ordnance Survey Vector Map Local that was hosted on the Geograph website and which was entitled the Interactive Coverage Map, or from surveying with the Trimble GeoXH 6000, or from LIDAR analysis, and for this deletion that affected the Humps the email I posted on the Tump Googlegroups forum in relation to this hill was dated 12.11.20.

The listing of Humps was published in book format by Lulu in 2009 and entitled More Relative Hills of Britain, its author; Mark Jackson gives credit to a number of people who contributed toward the formation of this list, these include; Eric Yeaman, Alan Dawson, Clem Clements, Rob Woodall, Bernie Hughes, Pete Ridges and others.  When the list was published in book format there were 2987 Humps listed with their criteria being any British hill that has 100m or more of drop, irrespective of their height.  Accompanying the main list is a sub category entitled Subhumps, with the criteria being any British hill that has 90m or more and below 100m of drop.

More Relative Hills of Britain by Mark Jackson

The details for this deletion appear below:

There has been a deletion to the listing of the Humps (HUndred Metre Prominences) instigated by LIDAR analysis initially conducted by Aled Williams and then independently by Joe Nuttall who produced a summit analysis programme based on heights and drops of hills produced by LIDAR, and as there was a discrepancy in bwlch position for these two studies LIDAR analysis was then conducted by Myrddyn Phillips.

LIDAR bwlch image of Werfa

The bwlch of Werfa

The name the hill is listed by is Werfa and it is adjoined to the Cymoedd group of hills, and it is positioned with the A4190 road to its north-east, and has the village of Abergwynfi towards the north-west.

Prior to this deletion this hill was listed as a Subhump with 90m of drop based on the 568m summit spot height adjoined to a triangulation pillar and which appears on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer maps and a bwlch height of c 478m based on interpolation of 10m contouring between 470m – 480m.

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

However, the advent of LIDAR has meant greater accuracy for summit and bwlch heights and their positions.  Currently LIDAR only covers the bwlch of this hill and analysis gives a natural bwlch height of 479.9m positioned at SS 91189 97075.  This re-assessment resulted in a recommendation of this hill being deleted from Subhump status with 88m of drop.

This summit of this hill was subsequently surveyed on the 17.04.21 by Myrddyn Phillips and Aled Williams using a Trimble GeoXH 6000, resulting in a 567.5m summit height and when coupled with the 479.9m bwlch height ascertained from LIDAR analysis, these values give this hill 87.5m of drop.

The Trimble GeoXH 6000 gathering data at the summit of Werfa

The listing of the Humps was updated with the deletion of this hill from Subhump status and this was augmented on the 06.02.21.

 

The full details for the hill are:

Name:  Werfa [Mynydd Llangeinwyr] (as listed in the Humps)

OS 1:50,000 map:  170

OS 1:25,000 map:  166

Summit Height:  568m (as listed in the Humps, with the Trimble GeoXH 6000 survey giving 567.5m)

Summit Grid Reference:  SS 91278 94773 (as listed in the Humps, with the Trimble GeoXH 6000 survey giving SS 91274 94767)

Bwlch Height:  480.0m (as listed in the Humps with independent LIDAR analysis giving 479.9m)

Bwlch Grid Reference:  SS 9118 9707 (as listed in the Humps with independent LIDAR analysis giving SS 91189 97075)

Drop:  88m (as listed in the Humps with the Trimble GeoXH 6000 summit survey and independent LIDAR bwlch analysis giving 87.5m)

 

Myrddyn Phillips (July 2021)

 

 

 

 

 

Mapping Mountains – Hill Reclassifications – Humps

Twyn y Waun (SO 082 070) – Recommended Subhump addition

This is the thirty first in a series of Hill Reclassification posts that detail hills whose status has either been altered in the listing of the Humps (HUndred Metre Prominences) through map study and / or surveys that I have instigated, or it is the recommendation that their status is altered.

The artificial summit of Twyn y Waun (SO 082 070)

Many preceding posts detailing these alterations to the Humps are retrospective as these hill reclassifications were either initiated from studying the Ordnance Survey Interactive Coverage Map that is hosted on the Geograph website, or initiated from a survey with the Trimble GeoXH 6000, and for the recommended addition that affects the Humps the survey of this hill took place on the 01.12.17.

The listing of Humps was published in book format by Lulu in 2009 and entitled More Relative Hills of Britain, its author; Mark Jackson gives credit to a number of people who contributed toward the formation of this list, these include; Eric Yeaman, Alan Dawson, Clem Clements, Rob Woodall, Bernie Hughes, Pete Ridges and others.  When the list was published in book format there were 2987 Humps listed with their criteria being any British hill that has 100m or more of drop, accompanying the main list is a sub category entitled Subhumps, with the criteria being any British hill that has 90m or more and below 100m of drop.

More Relative Hills of Britain by Mark Jackson

The details for the recommended reclassification appear below:

There has been a recommended reclassification to the listing of the Humps (HUndred Metre Prominences) instigated by a survey with the Trimble GeoXH 6000 which took place on the 01.12.17.

This hill has an intact natural summit and an artificial summit that now overshadows it and Mark Jackson lists this hill with 63m of drop based on an estimated c 451m height for the natural summit which has an uppermost 450m contour on the Ordnance Survey 1:50,000 Landranger map and the Interactive Coverage Map hosted on the Geograph website, and an estimated bwlch height of 388m based on bwlch contouring at 10m intervals and between 380m – 390m on the 1:25,000 Explorer map.  However, OS Maps which is the recent replacement for OS Get-a-map gives bwlch contouring at 5m intervals and between 375m – 380m, with the latter height taking in the width of a road and indicating an estimated bwlch height of c 380m, which if the artificial summit was taken for that of the hill gives this hill c 96m of drop.

However, it was not until LIDAR became available that the bwlch 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 natural summit of Twyn y Waun is now overshadowed by its artificial summit

Twyn y Waun is adjoined to the Y Cymoedd – dwyreiniol group of hills and is positioned between the town of Merthyr Tudful (Merthyr Tydfil) to its west and Rhymni (Rhymney) to its east and has the A 465 Heads of the Valleys Road to its north-west.

Therefore, if the artificial summit is taken as that for the hill it is recommended that its status is amended to that of Subhump.

The full details for the hill are:

Name:  Twn y Waun (as listed in the Tumps)

Summit Height:  451m (as listed in the Tumps) (476.0m [converted to OSGM15] artificial summit)

OS 1:50,000 map:  160

OS 1:25,000 map:  12, 166

Summit Grid Reference:  SO 08457 07348 (as listed in the Tumps) (artificial summit at SO 08209 07041)

Drop:  63m (as listed in the Tumps) (96.0m Trimble GeoXH 6000 summit and LIDAR bwlch, artificial summit)

Myrddyn Phillips (January 2018)

Mapping Mountains – Hill Reclassifications – Humps

Pen y Graig-fawr (SN 773 996) – Recommended Subhump deletion

This is the thirtieth in a series of Hill Reclassification posts that detail hills whose status has either been altered in the listing of the Humps (HUndred Metre Prominences) through map study and / or surveys that I have instigated, or it is the recommendation that their status is altered.

Pen y Graig-fawr (SN 773 996)

Many preceding posts detailing these alterations to the Humps are retrospective as these hill reclassifications were either initiated from studying the Ordnance Survey enlarged mapping that is hosted on the Geograph website, or initiated from a survey with the Trimble GeoXH 6000, and for the recommended reclassification that affects the Humps the survey of this hill took place on the 29.10.17.

The listing of Humps was published in book format by Lulu in 2009 and entitled More Relative Hills of Britain, its author; Mark Jackson gives credit to a number of people who contributed toward the formation of this list, these include; Eric Yeaman, Alan Dawson, Clem Clements, Rob Woodall, Bernie Hughes, Pete Ridges and others.  When the list was published in book format there were 2987 Humps listed with their criteria being any British hill that has 100m or more of drop, accompanying the main list is a sub category entitled Subhumps, with the criteria being any British hill that has 90m or more and below 100m of drop.

More Relative Hills of Britain by Mark Jackson

The details for the recommended reclassification appear below:

There has been a recommended reclassification to the listing of the Humps (HUndred Metre Prominences) instigated by a survey with the Trimble GeoXH 6000 which took place on the 29.10.17.

Mark Jackson lists this hill with 99m of drop based on the 217m summit spot height given to a triangulation pillar that appears on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map and an estimated bwlch height of 118m based on bwlch contouring at 10m intervals and between 120m – 130m. 

The height of the above estimated bwlch is at odds with Ordnance Survey contouring.

Interpolation of 10m bwlch contouring suggests a height of c 217m, giving this hill the minimum of c 90m of drop for continued Subhump status.  However, OS Maps which has recently replaced OS Get-a-map gives bwlch contouring at 5m intervals and between 125m – 130m, with interpolation suggesting a height of c 128m, which would give this hill c 89m of drop.

Pen y Graig-fawr also has an adjacent summit named Copa Shon (SN 781 993) of equal 217m map height, with this summit height appearing on the Ordnance Survey 1:50,000 Landranger map and the enlarged mapping that is hosted on the Geograph website.

Copa Shon (SN 781 993)

These two equal map heighted summits are adjoined to the Pumlumon group of hills and are situated between the A 489 road to the north and the Afon Dulas to the south, and they are positioned with the town of Machynlleth to the west north-west and the small community of Penegoes towards the north.

These two hills were surveyed using a Trimble GeoXH 6000 by Myrddyn Phillips on the 29.10.17 resulting in a 216.833m (converted to OSGM15) summit height for Pen y Graig-fawr and a 217.336m (converted to OSGM15) summit height for Copa Shon, therefore as Copa Shon is higher than Pen y Graig-fawr their respective critical bylchau are swapped.  Each bwlch was surveyed using the Trimble GeoXH 6000 with the following results:

127.885m (converted to OSGM15) at SN 80033 98740

182.393m (converted to OSGM15) at SN 77600 99583

Gathering data with the Trimble GeoXH 6000 at the summit of Pen y Graig-fawr

Gathering data with the Trimble GeoXH 6000 at the summit of Copa Shon

Gathering data at the critical bwlch

The bwlch positioned at SN 800 987 is that for the higher of these two summits and therefore as Pen y Graig-fawr is lower than Copa Shon it is recommended that its Subhump status is swapped to the higher summit, but as Copa Shon only has 89.5m of drop it is recommended that the status of Subhump is deleted.

The full details for the hill listed as a Subhump are:

Name:  Pen y Graig-fawr

Summit Height:  216.8m (converted to OSGM15) (Copa Shon is higher)

OS 1:50,000 map:  135

OS 1:25,000 map:  23, 215

Summit Grid Reference:  SN 773 996 (as listed in the Humps)

Drop:  99m (as listed in the Humps) (surveyed as having only 34.4m of drop with Copa Shon having 89.5m of drop)

Myrddyn Phillips (January 2018)