Thursday 15 April 2021

Mapping Mountains – Hill Reclassifications – The Welsh P15s


The Welsh P15s – Hill Reclassifications

The Welsh P15s are all Welsh hills that have a minimum of 15m of drop, irrespective of their height.  Accompanying the main P15 list is a sub list entitled; The Welsh Sub-P15s, with the qualification to this sub category being all Welsh hills with 14m or more and below 15m of drop.

The list is authored by Myrddyn Phillips and the posts that have appeared on Mapping Mountains detailing the additions, reclassifications and deletions to the main P15 list and the sub list that are below P20 and therefore documented in other lists, appear below presented chronologically in receding order.






Mapping Mountains - Hill Reclassifications - The Welsh P15s

Comin Gwauncaegurwen (SN 711 123) – Welsh P15 addition (33rd reclassification)

Significant Height Revisions post for Comin Gwauncaegurwen

Significant Name Changes post for Comin Gwauncaegurwen

 

There has been an addition to the list of The Welsh P15s, with the summit height, bwlch height and their locations, the drop and status of the hill derived from LIDAR analysis conducted by Myrddyn Phillips. 

LIDAR image of Comin Gwauncaegurwen (SN 711 123)

The criteria for the list that this addition applies to are:

The Welsh P15s – Welsh hills with 15m minimum drop, irrespective of their height, with an accompanying sub list entitled the Welsh Sub-P15s, with the criteria for this sub category being all Welsh hills with 14m or more and below 15m of drop.  The list is authored by Myrddyn Phillips, with the Introduction to the list appearing on Mapping Mountains on the 10th May 2019. 

The Welsh P15s by Myrddyn Phillips

The name the hill is listed by is Comin Gwauncaegurwen and this was derived from the Tithe map with the language protocol also used, and it is adjoined to the Mynydd Du group of hills, which are situated in the southern part of South Wales (Region B, Sub-Region B5), and it is positioned with the A4068 road to its north-east, the A4069 road to its north-west and a minor road to its south, and has the village of Brynaman towards the north.

When the listing that became known as The Welsh P15s was being compiled, this hill was not included in the main P15 list or the accompanying P14 sub list, as with no significant contours of note on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map it was difficult to know whether any hill of note existed. 

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

One of the mapping resources now available online is the WalkLakes website which hosts an interactive map originated from the Ordnance Survey Open Data programme.  This map has many spot heights not on other publicly available maps and a 216m spot height is given on the summit area of this hill. 

Extract from the interactive mapping hosted on the WalkLakes website

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

Therefore, the addition of this hill to Welsh P15 status is due to LIDAR analysis, resulting in a 216.6m summit height and a 196.6m bwlch height, with these values giving this hill 19.98m of drop, which is sufficient for it to be included in the main list of The Welsh P15s. 

 

The full details for the hill are: 

Group:  Mynydd Du 

Name:  Comin Gawuncaegurwen 

OS 1:50,000 map:  160

Summit Height:  216.6 (LIDAR)                                                           

Summit Grid Reference:  SN 71158 12343 (LIDAR) 

Bwlch Height:  196.6m (LIDAR) 

Bwlch Grid Reference:  SN 71330 12592 & SN 71332 12592 (LIDAR) 

Drop:  19.98m (LIDAR) 

 

Myrddyn Phillips (April 2024)




Mapping Mountains - Hill Reclassifications - The Welsh P15s

Y Garreg Las (SN 768 098) – Welsh Sub-P15 reclassified to Welsh P15 (32nd reclassification)

Summit Relocations post for Y Garreg Las

Significant Name Changes post for Y Garreg Las

 

There has been a reclassification to the list of The Welsh P15s, with the summit height, bwlch height and their locations, the drop and status of the hill derived from LIDAR analysis conducted by Myrddyn Phillips. 

LIDAR image of Y Garreg Las (SN 768 098)

The criteria for the list that this reclassification applies to are:

The Welsh P15s – Welsh hills with 15m minimum drop, irrespective of their height, with an accompanying sub list entitled the Welsh Sub-P15s, with the criteria for this sub category being all Welsh hills with 14m or more and below 15m of drop.  The list is authored by Myrddyn Phillips, with the Introduction to the list appearing on Mapping Mountains on the 10th May 2019. 

The Welsh P15s by Myrddyn Phillips

The name the hill is now listed by is Y Garreg Las and this was derived from the Tithe map and it is adjoined to the Mynydd Du group of hills, which are situated in the southern part of South Wales (Region B, Sub-Region B5), and it is positioned with a minor road to its immediate north-east, and west, the A4068 road farther to its north-east and the A4067 road to its south-east, and has the community of Y Gurnos towards the east south-east. 

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

When the listing that became known as The Welsh P15s was being compiled, this hill was included in the P14 sub list with an estimated c 14m of drop, based on the 157m summit spot height that appeared on the Ordnance Survey Vector Map Local hosted on the Geograph website and which was entitled the Interactive Coverage Map and an estimated c 143m bwlch height, based on interpolation of 5m contouring between 140m – 145m that appeared on the OS Maps website.  Latterly the interactive mapping hosted on the WalkLakes website gives this hill a 158m summit spot height. 

Extract from the interactive mapping hosted on the WalkLakes website

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

Therefore, the reclassification of this hill from Welsh Sub-P15 status is due to LIDAR analysis, resulting in a 158.5m summit height and a 141.7m bwlch height, with these values giving this hill 16.75m of drop, which is sufficient for it to be included in the main list of The Welsh P15s. 

 

The full details for the hill are: 

Group:  Mynydd Du 

Name:  Y Garreg Las 

OS 1:50,000 map:  160

Summit Height:  158.5m (LIDAR)                                                           

Summit Grid Reference:  SN 76803 09804 (LIDAR) 

Bwlch Height:  141.7m (LIDAR) 

Bwlch Grid Reference:  SN 76797 09723 (LIDAR) 

Drop:  16.75m (LIDAR) 

 

Myrddyn Phillips (March 2024)

 



Mapping Mountains - Hill Reclassifications - The Welsh P15s

Pt. 357.3m (SN 995 612) – Welsh P15 reclassified to Welsh Sub-P15 (31st reclassification)

Survey post for Pt. 357.3m

 

There has been a reclassification to the list of The Welsh P15s, with the summit height, bwlch height and their locations, the drop and status of the hill derived from LIDAR analysis conducted by Myrddyn Phillips. 

LIDAR image of Pt. 357.3m (SN 995 612)

The criteria for the list that this reclassification applies to are:

The Welsh P15s – Welsh hills with 15m minimum drop, irrespective of their height, with an accompanying sub list entitled the Welsh Sub-P15s, with the criteria for this sub category being all Welsh hills with 14m or more and below 15m of drop.  The list is authored by Myrddyn Phillips, with the Introduction to the list appearing on Mapping Mountains on the 10th May 2019. 

The Welsh P15s by Myrddyn Phillips

The hill is being listed by the point (Pt. 357.3m) notation as an appropriate name for it either through local enquiry and/or historic research has not been found by the author, and it is adjoined to the Drygarn Fawr group of hills, which are situated in the central part of the South Wales Region (Region B, Sub-Region B1), and it is positioned with a minor road to its immediate west and the A470 road to its north-east, and has the town of Llandrindod Wells towards the east.

When the listing that became known as The Welsh P15s was being compiled, this hill was included in the main P15 list with 15m of drop, based on the 358m summit spot height and the 343m bwlch spot height that appear on the Ordnance Survey 1:25,000 Explorer map. 

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

Therefore, the reclassification of this hill to Welsh Sub-P15 status is due to LIDAR analysis, resulting in a 357.3m summit height and a 342.9m bwlch height, with these values giving this hill 14.4m of drop, which is insufficient for it to be included in the main list of The Welsh P15s. 

 

The full details for the hill are: 

Group:  Drygarn Fawr 

Name:  Pt. 357.3m 

OS 1:50,000 map:  147

Summit Height:  357.3m (LIDAR)                                                           

Summit Grid Reference:  SN 99517 61281 (LIDAR) 

Bwlch Height:  342.9m (LIDAR) 

Bwlch Grid Reference:  SN 99418 61379 (LIDAR) 

Drop:  14.4m (LIDAR) 

 

Myrddyn Phillips (January 2023)

 



Mapping Mountains - Hill Reclassifications - The Welsh P15s

Tyn Ffynnon (SN 549 487) – Welsh P15 reclassified to Welsh Sub-P15 (30th reclassification)

Summit Relocations post for Tyn Ffynnon

Significant Name Changes post for Tyn Ffynnon

 

There has been a reclassification to the list of The Welsh P15s, with the summit height, bwlch height and their locations, the drop and status of the hill derived from LIDAR analysis conducted by Myrddyn Phillips. 

LIDAR image of Tyn Ffynnon (SN 549 487)

The criteria for the list that this reclassification applies to are:

The Welsh P15s – Welsh hills with 15m minimum drop, irrespective of their height, with an accompanying sub list entitled the Welsh Sub-P15s, with the criteria for this sub category being all Welsh hills with 14m or more and below 15m of drop.  The list is authored by Myrddyn Phillips, with the Introduction to the list appearing on Mapping Mountains on the 10th May 2019. 

The Welsh P15s by Myrddyn Phillips

The name the hill is listed by is Tyn Ffynnon and this was derived from the Tithe map and it is adjoined to the Mynydd Bach group of hills, which are situated in the western part of South Wales (Region B, Sub-Region B1), and it is positioned encircled by minor roads, with the B4337 road farther to its west, the A475 road farther to its south and the A482 road farther to its east, and has the town of Llanbedr Pont Steffan (Lampeter) towards the east south-east.

When the listing that became known as The Welsh P15s was being compiled, this hill was included in the main P15 list with an estimated c 16m of drop, based on the 224m summit spot height that appears on the Ordnance Survey 1:50,000 Landranger map and 1:25,000 Explorer map and an estimated c 208m bwlch height, based on interpolation of 5m contouring between 205m - 210m that appeared on the Ordnance Survey Vector Map Local hosted on the Geograph website and which was entitled the Interactive Coverage Map. 

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

Therefore, the reclassification of this hill to Welsh Sub-P15 status is due to LIDAR analysis, resulting in a 224.3m summit height and a 210.0m bwlch height, with these values giving this hill 14.3m of drop, which is insufficient for it to be included in the main list of The Welsh P15s. 

 

The full details for the hill are: 

Group:  Mynydd Bach 

Name:  Tyn Ffynnon 

OS 1:50,000 map:  146

Summit Height:  224.3m (LIDAR)                                                           

Summit Grid Reference:  SN 54956 48738 (LIDAR) 

Bwlch Height:  210.0m (LIDAR) 

Bwlch Grid Reference:  SN 55631 48720 (LIDAR) 

Drop:  14.3m (LIDAR) 

 

Myrddyn Phillips (December 2022)

 



Mapping Mountains - Hill Reclassifications - The Welsh P15s

Moel y Crio (SJ 199 696) – Welsh Sub-P15 reclassified to Welsh P15 (29th reclassification)

Survey post for Moel y Crio


There has been a reclassification to the list of The Welsh P15s, with the summit height, bwlch height and their locations, the drop and status of the hill derived from a Trimble GeoXH 6000 survey conducted by Myrddyn Phillips with assistance from Mark Trengove.

 

Moel y Crio (SJ 199 696)


The criteria for the list that this reclassification applies to are: 

The Welsh P15s – Welsh hills with 15m minimum drop, irrespective of their height, with an accompanying sub list entitled the Welsh Sub-P15s, with the criteria for this sub category being all Welsh hills with 14m or more and below 15m of drop.  The list is authored by Myrddyn Phillips, with the Introduction to the list appearing on Mapping Mountains on the 10th May 2019. 

The Welsh P15s by Myrddyn Phillips

The name the hill is listed by is Moel y Crio, and it is adjoined to the Moel y Gamelin group of hills, which are situated in the north-eastern part of North Wales (Region A, Sub-Region A2), and it is positioned encircled by minor roads with the B5123 road farther to its east, and has the town of Yr Wyddgrug (Mold) towards the south-east.

When the listing that became known as The Welsh P15s was being compiled, this hill was included in the P14 sub list with an estimated c 14m of drop, based on the 292m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and an estimated c 278m bwlch height, based on interpolation of 5m contouring between 275m – 280m that appear on the Ordnance Survey 1:25,000 Explorer map.

 

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


However, it was not until this hill was surveyed with the Trimble GeoXH 6000 that an accurate height for both its summit and connecting bwlch, and hence its drop could be ascertained.

 

The Trimble GeoXH 6000 gathering data at the summit of Moel y Crio

The Trimble GeoXH 6000 gathering data at the bwlch of Moel y Crio


Therefore, the reclassification of this hill from Welsh Sub-P15 status is due to a Trimble GeoXH 6000 survey, resulting in a 297.5m summit height and a 276.8m bwlch height, with these values giving this hill 20.7m of drop, which is sufficient for it to be included in the main list of The Welsh P15s. 

 

The full details for the hill are: 

Group:  Moel y Gamelin 

Name:  Moel y Crio 

OS 1:50,000 map:  116

Summit Height:  297.5m (converted to OSGM15) 

Summit Grid Reference:  SJ 19988 69614 

Bwlch Height:  276.8m (converted to OSGM15) 

Bwlch Grid Reference:  SJ 20406 69385 

Drop:  20.7m 

 

Myrddyn Phillips (August 2022)




Mapping Mountains - Hill Reclassifications - The Welsh P15s

Craignant Hill (SJ 118 164) – Welsh Sub-P15 reclassified to Welsh P15 (28th reclassification)

Survey post for Craignant Hill

Significant Name Changes post for Craignant Hill


There has been a reclassification to the list of The Welsh P15s, with the summit height, bwlch height and their locations, the drop and status of the hill derived from a Trimble GeoXH 6000 survey conducted by Myrddyn Phillips. 

Craignant Hill (SJ 118 164)

The criteria for the list that this reclassification applies to are:The Welsh P15s – Welsh hills with 15m minimum drop, irrespective of their height, with an accompanying sub list entitled the Welsh Sub-P15s, with the criteria for this sub category being all Welsh hills with 14m or more and below 15m of drop.  The list is authored by Myrddyn Phillips, with the Introduction to the list appearing on Mapping Mountains on the 10th May 2019. 

The Welsh P15s by Myrddyn Phillips

The name the hill is listed by is Craignant Hill and this was derived by local enquiry and it is adjoined to the Foel Cedig group of hills, which are situated in the southern part of North Wales (Region A, Sub-Region A3), and it is positioned encircled by minor roads, with the B4393 road farther to its north-west, the B4382 road farther to its west, the A495 road farther to its south-east and the A490 road farther to its north-east, and has the town of Llanfyllin towards the north-east.

When the listing that became known as The Welsh P15s was being compiled, this hill was included in the P14 sub list with an estimated c 14m of drop, based on the 329m summit spot height that appeared on the Ordnance Survey Vector Map Local hosted on the Geograph website and which was entitled the Interactive Coverage Map and an estimated c 315m bwlch height based on interpolation of 10m contouring that appears on the Ordnance Survey 1:25,000 Explorer map. 

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

However, it was not until this hill was surveyed with the Trimble GeoXH 6000 that an accurate height for both its summit and connecting bwlch, and hence its drop could be ascertained. 

The Trimble GeoXH 6000 gathering data at the bwlch of Craignant Hill

The Trimble GeoXH 6000 gathering data at the summit of Craignant Hill

Therefore, the reclassification of this hill from Welsh Sub-P15 status is due to a Trimble GeoXH 6000 survey, resulting in a 329.3m summit height and a 311.4m bwlch height, with these values giving this hill 18.0m of drop, which is sufficient for it to be included in the main list of The Welsh P15s. 

 

The full details for the hill are: 

Group:  Foel Cedig 

Name:  Craignant Hill 

OS 1:50,000 map:  125

Summit Height:  329.3m (converted to OSGM15)                                                           

Summit Grid Reference:  SJ 11893 16416 

Bwlch Height:  311.4m (converted to OSGM15) 

Bwlch Grid Reference:  SJ 11967 16505 

Drop:  18.0 

 

Myrddyn Phillips (August 2022)

 



Mapping Mountains - Hill Reclassifications - The Welsh P15s

Pt. 19m (SH 218 796) – Welsh P15 addition (27th reclassification)


There has been an addition to the list of The Welsh P15s, with the summit height, bwlch height and their locations, the drop and status of the hill derived from detail on contemporary maps produced from Ordnance Survey data. 

The criteria for the list that this addition applies to are: 

The Welsh P15s – Welsh hills with 15m minimum drop, irrespective of their height, with an accompanying sub list entitled the Welsh Sub-P15s, with the criteria for this sub category being all Welsh hills with 14m or more and below 15m of drop.  The list is authored by Myrddyn Phillips, with the Introduction to the list appearing on Mapping Mountains on the 10th May 2019. 

The Welsh P15s by Myrddyn Phillips

The hill is being listed by the point (Pt. 19m) notation as an appropriate name for it either through local enquiry and / or historic research has not been found by the author, and it is adjoined to the Ynys Môn group of hills, which are situated in the north-western part of North Wales (Region A, Sub-Region A1), and it is positioned with the coast to its immediate south-west and a minor road to its north-east, and has the town of Caergybi (Holyhead) towards the north-east. 

When the listing that became known as The Welsh P15s was being compiled, this hill was not included in either the main P15 list or the accompanying P14 sub list, as the contours that appear on the Ordnance Survey 1:25,000 Explorer map are hard to decipher. 

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

Since the start of this list’s compilation 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 old Ordnance Survey Vector Map Local hosted on the Geograph website and which was entitled the Interactive Coverage Map and the interactive mapping on the Magic Maps website. 

The details for this hill were re-assessed against the large scale mapping that has replaced the Ordnance Survey mapping available on the Geograph website and the interactive mapping available of the Magic Maps website.  The former gives this hill a 19m summit spot height and the latter an 18m summit spot height.  These spot heights compliment 5m contouring available online with the 19m height prioritised. 

Extract from the Ordnance Survey mapping hosted on the Geograph website

Therefore, the addition of this hill to Welsh P15 status is due to detail on contemporary maps produced from Ordnance Survey data, resulting in a 19m summit height and an estimated c 2m bwlch height, with these values giving this hill an estimated c 17m 0f drop, which is sufficient for it to be classified in the main list of The Welsh P15s. 

 

The full details for the hill are: 

Group:  Ynys Môn 

Name:  Pt. 19m 

OS 1:50,000 map:  114

Summit Height:  19m (spot height)                                                           

Summit Grid Reference:  SH 21889 79633 (spot height) 

Bwlch Height:  c 2m (interpolation) 

Bwlch Grid Reference:  SH 21898 79642 (interpolation) 

Drop:  c 17m (spot height summit and interpolated bwlch) 

 

Myrddyn Phillips (November 2021)

 



Mapping Mountains - Hill Reclassifications - The Welsh P15s

Pen Las Rock (SH 208 815) – Welsh P15 addition (26th reclassification)


There has been an addition to the list of The Welsh P15s, with the summit height, bwlch height and their locations, the drop and status of the hill derived from detail on contemporary maps produced from Ordnance Survey data. 

The criteria for the list that this addition applies to are: 

The Welsh P15s – Welsh hills with 15m minimum drop, irrespective of their height, with an accompanying sub list entitled the Welsh Sub-P15s, with the criteria for this sub category being all Welsh hills with 14m or more and below 15m of drop.  The list is authored by Myrddyn Phillips, with the Introduction to the list appearing on Mapping Mountains on the 10th May 2019. 

The Welsh P15s by Myrddyn Phillips

The name the hill is listed by is Pen Las Rock and it is adjoined to the Ynys Môn group of hills, which are situated in the north-western part of North Wales (Region A, Sub-Region A1), and it is positioned with the coast to its immediate west and a minor road to its north-east, and has the town of Caergybi (Holyhead) towards the east. 

When the listing that became known as The Welsh P15s was being compiled, this hill was not included in either the main P15 list or the accompanying P14 sub list, as the contours that appear on the Ordnance Survey 1:25,000 Explorer map are hard to decipher. 

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

Since the start of this list’s compilation 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 old Ordnance Survey Vector Map Local hosted on the Geograph website and which was entitled the Interactive Coverage Map and the interactive mapping on the Magic Maps website. 

The details for this hill were re-assessed against the large scale mapping that has replaced the Ordnance Survey mapping available on the Geograph website and the interactive mapping available of the Magic Maps website.  The former gives this hill a 50m summit spot height and the latter a 49m summit spot height.  The 50m spot height compliments 5m contouring available online, with this also giving bwlch contouring between 30m – 35m and which has been estimated as c 33m in height. 

Extract from the Ordnance Survey mapping hosted on the Geograph website 

Therefore, the addition of this hill to Welsh P15 status is due to detail on contemporary maps produced from Ordnance Survey data, resulting in a 50m summit height and an estimated c 33m bwlch height, with these values giving this hill an estimated c 17m 0f drop, which is sufficient for it to be classified in the main list of The Welsh P15s. 

 

The full details for the hill are: 

Group:  Ynys Môn 

Name:  Pen Las Rock 

OS 1:50,000 map:  114

Summit Height:  50m (spot height)                                                           

Summit Grid Reference:  SH 20813 81594 (spot height) 

Bwlch Height:  c 33m (interpolation) 

Bwlch Grid Reference:  SH 20829 81624 (interpolation) 

Drop:  c 17m (spot height summit and interpolated bwlch) 

 

Myrddyn Phillips (October 2021)

 



Mapping Mountains - Hill Reclassifications - The Welsh P15s

Cerrig Engan (SH 405 734) – Welsh P15 addition (25th reclassification)

Significant Name Changes post for Cerrig Engan


There has been an addition to the list of The Welsh P15s, with the summit height, bwlch height and their locations, the drop and status of the hill derived from LIDAR analysis conducted by Myrddyn Phillips. 

LIDAR image of Cerrig Engan (SH 405 734)

The criteria for the list that this addition applies to are: 

The Welsh P15s – Welsh hills with 15m minimum drop, irrespective of their height, with an accompanying sub list entitled the Welsh Sub-P15s, with the criteria for this sub category being all Welsh hills with 14m or more and below 15m of drop.  The list is authored by Myrddyn Phillips, with the Introduction to the list appearing on Mapping Mountains on the 10th May 2019. 

The Welsh P15s by Myrddyn Phillips

The name the hill is listed by is Cerrig Engan and this was derived from the Tithe map, and it is adjoined to the Ynys Môn group of hills, which are situated in the north-western part of North Wales (Region A, Sub-Region A1), and it is positioned with the coast to its west, minor roads to its north-east, west and south, the A55 and A5 roads farther to its north and the B4422 road farther to its south-east, and has the town of Llangefni towards the east north-east. 

When the listing that became known as The Welsh P15s was being compiled, this hill was not included in either the main P15 list or the accompanying P14 sub list, but it was documented with an estimated c 13m of drop, based on an estimated c 70m summit height and an estimated c 57m bwlch height, with both heights based on interpolation of 5m contouring that appear on the Ordnance Survey 1:25,000 Explorer map. 

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

Therefore, the addition of this hill to Welsh P15 status is due to LIDAR analysis, resulting in a 69.4m summit height and a 54.4m bwlch height, with these values giving this hill 15.0m of drop, which is sufficient for it to be included in the main list of The Welsh P15s. 

 

The full details for the hill are: 

Group:  Ynys Môn 

Name:  Cerrig Engan 

OS 1:50,000 map:  114, 115

Summit Height:  69.4m (LIDAR)                                                           

Summit Grid Reference:  SH 40529 73455 (LIDAR) 

Bwlch Height:  54.4m (LIDAR) 

Bwlch Grid Reference:  SH 40431 73497 (LIDAR) 

Drop:  15.0m (LIDAR) 

 

Myrddyn Phillips (October 2021)

 



Mapping Mountains - Hill Reclassifications - The Welsh P15s

Tywyn Niwbwrch (SH 419 625) – Welsh P15 addition (24th reclassification)

Significant Height Revisions post for Tywyn Niwbwrch


There has been an addition to the list of The Welsh P15s, with the summit height, bwlch height and their locations, the drop and status of the hill derived from LIDAR analysis conducted by Myrddyn Phillips. 

LIDAR image of Tywyn Niwbwrch (SH 419 625)

The criteria for the list that this addition applies to are: 

The Welsh P15s – Welsh hills with 15m minimum drop, irrespective of their height, with an accompanying sub list entitled the Welsh Sub-P15s, with the criteria for this sub category being all Welsh hills with 14m or more and below 15m of drop.  The list is authored by Myrddyn Phillips, with the Introduction to the list appearing on Mapping Mountains on the 10th May 2019. 

The Welsh P15s by Myrddyn Phillips

The name the hill is listed by is Tywyn Niwbwrch and it is adjoined to the Ynys Môn group of hills, which are situated in the north-western part of North Wales (Region A, Sub-Region A1), and it is positioned with the coast to its south-west and the A4080 road to its north-east, and has the village of Niwbwrch (Newborough) towards the north. 

When the listing that became known as The Welsh P15s was being compiled, this hill was not included in either the main P15 list or the accompanying P14 sub list, as it possessed no contours of significance on either the Ordnance Survey 1:50,000 Landranger or the 1:25,000 Explorer map. 

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

Therefore, the addition of this hill to Welsh P15 status is due to LIDAR analysis, resulting in a 26.9m summit height and an 8.4m bwlch height, with these values giving this hill 18.4m of drop, which is sufficient for it to be included in the main list of The Welsh P15s. 

 

The full details for the hill are: 

Group:  Ynys Môn 

Name:  Tywyn Niwbwrch 

OS 1:50,000 map:  114, 115

Summit Height:  26.9m (LIDAR)                                                           

Summit Grid Reference:  SH 41937 62552 (LIDAR) 

Bwlch Height:  8.4m (LIDAR) 

Bwlch Grid Reference:  SH 41804 62760 (LIDAR) 

Drop:  18.4m (LIDAR) 

 

Myrddyn Phillips (October 2021)

 



Mapping Mountains - Hill Reclassifications - The Welsh P15s

Caer Helen (SH 325 780) – Welsh P15 addition (23rd reclassification)

Significant Name Changes post for Caer Helen


There has been an addition to the list of The Welsh P15s, with the summit height, bwlch height and their locations, the drop and status of the hill derived from LIDAR analysis conducted by Myrddyn Phillips. 

LIDAR image of Caer Helen (SH 325 780)

The criteria for the list that this addition applies to are: 

The Welsh P15s – Welsh hills with 15m minimum drop, irrespective of their height, with an accompanying sub list entitled the Welsh Sub-P15s, with the criteria for this sub category being all Welsh hills with 14m or more and below 15m of drop.  The list is authored by Myrddyn Phillips, with the Introduction to the list appearing on Mapping Mountains on the 10th May 2019. 

The Welsh P15s by Myrddyn Phillips

The name the hill is listed by is Caer Helen and this was derived from the Ordnance Survey series of Six-Inch maps and it is adjoined to the Ynys Môn group of hills, which are situated in the north-western part of North Wales (Region A, Sub-Region A1), and it is positioned with the coast to its west, the A5 and A55 roads to its north and minor roads to its west and south, and has the village of Llanfiangel-yn-Nhywyn towards the south-west. 

When the listing that became known as The Welsh P15s was being compiled, this hill was not included in either the main P15 list or the accompanying P14 sub list, but it was documented with an estimated c 13m of drop, based on the 34m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and an estimated c 21m bwlch height, based on interpolation of 5m contouring between 20m – 25m. 

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

Therefore, the addition of this hill to Welsh P15 status is due to LIDAR analysis, resulting in a 33.9m summit height and a 17.4m bwlch height, with these values giving this hill 16.5m of drop, which is sufficient for it to be included in the main list of The Welsh P15s. 

 

The full details for the hill are: 

Group:  Ynys Môn 

Name:  Caer Helen 

OS 1:50,000 map:  114

Summit Height:  33.9m (LIDAR)                                                           

Summit Grid Reference:  SH 32589 78052 (LIDAR) 

Bwlch Height:  17.4m (LIDAR) 

Bwlch Grid Reference:  SH 32770 78215 (LIDAR) 

Drop:  16.5m (LIDAR) 

 

Myrddyn Phillips (October 2021)

 



Mapping Mountains - Hill Reclassifications - The Welsh P15s

Frigan (SH 483 845) – Welsh Sub-P15 deletion (22nd reclassification)

Significant Name Changes post for Frigan


There has been a deletion to the list of The Welsh P15s, with the summit height, bwlch height and their locations, the drop and status of the hill derived from LIDAR analysis conducted by Myrddyn Phillips. 

LIDAR image of Frigan (SH 483 845)

The criteria for the list that this deletion applies to are: 

The Welsh P15s – Welsh hills with 15m minimum drop, irrespective of their height, with an accompanying sub list entitled the Welsh Sub-P15s, with the criteria for this sub category being all Welsh hills with 14m or more and below 15m of drop.  The list is authored by Myrddyn Phillips, with the Introduction to the list appearing on Mapping Mountains on the 10th May 2019. 

The Welsh P15s by Myrddyn Phillips

The name the hill is listed by is Frigan and this was derived from the Tithe map, and it is adjoined to the Ynys Môn group of hills, which are situated in the north-western part of North Wales (Region A, Sub-Region A1), and it is positioned with the coast to its east, minor roads to its north, west and south, and the A5025 road to its north-east, and has the village of Moelfre towards the north-east. 

When the listing that became known as The Welsh P15s was being compiled, this hill was included in the P14 sub list with 14m of drop, based on the 98m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and the 84m bwlch spot height that appeared on the Ordnance Survey Vector Map Local hosted on the Geograph website and which was entitled the Interactive Coverage Map. 

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

Therefore, the deletion of this hill from Welsh Sub-P15 status is due to LIDAR analysis, resulting in a 97.8m summit height and an 86.3m bwlch height, with these values giving this hill 11.5m 0f drop, which is insufficient for it to be classified as a Welsh Sub-P15. 

 

The full details for the hill are: 

Group:  Ynys Môn 

Name:  Frigan 

OS 1:50,000 map:  114, 115

Summit Height:  97.8m (LIDAR)                                                           

Summit Grid Reference:  SH 48325 84509 (LIDAR) 

Bwlch Height:  86.3m (LIDAR) 

Bwlch Grid Reference:  SH 48653 84477 (LIDAR) 

Drop:  11.5m (LIDAR) 

 

Myrddyn Phillips (October 2021)

 

 


Mapping Mountains - Hill Reclassifications - The Welsh P15s

Ffridd Cae Crydd (SN 749 976) – Welsh Sub-P15 reclassified to 200m Twmpau (21st reclassification)

Survey post for Ffridd Cae Crydd


There has been a reclassification to the list of The Welsh P15s and the 200m Twmpau, with the summit height, bwlch height and their locations, the drop and status of the hill confirmed by LIDAR analysis and a subsequent Trimble GeoXH 6000 survey conducted by Myrddyn Phillips. 

Ffridd Cae Crydd (SN 749 976)

The criteria for the two listings that this reclassification applies to are: 

The Welsh P15s – Welsh hills with 15m minimum drop, irrespective of their height, with an accompanying sub list entitled the Welsh Sub-P15s, with the criteria for this sub category being all Welsh hills with 14m or more and below 15m of drop.  The list is authored by Myrddyn Phillips, with the Introduction to the list appearing on Mapping Mountains on the 10th May 2019. 

The Welsh P15s by Myrddyn Phillips

200m Twmpau – Welsh hills at or above 200m and below 300m in height that have 30m minimum drop, with an accompanying sub list entitled the 200m Sub-Twmpau with the criteria for this sub category being all Welsh hills at or above 200m and below 300m in height with 20m or more and below 30m of drop, with the word Twmpau being an acronym standing for thirty welsh metre prominences and upward. 

The 200m Twmpau by Myrddyn Phillips

The name the hill is listed by is Ffridd Cae Crydd and it is adjoined to the Pumlumon group of hills, which are situated in the north-western part of Mid and West Wales (Region B, Sub-Region B2), and it is positioned with the A489 road to its north and minor roads to its west, south and east, and has the town of Machynlleth towards the north.

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

When the listing that became known as The Welsh P15s was being compiled, this hill was included in the P14 sub list with an estimated c 14m of drop, based on an estimated c 271m summit height and an estimated c 257m bwlch height, with both heights based on interpolation of 10m contouring that appear on the Ordnance Survey 1:25,000 Explorer map.  With an adjacent hill listed as Ffridd Eithaf (SN 745 977) given a summit height of 272m based on the spot height that appears on the contemporary Ordnance Survey 1:25,000 Explorer map. 

LIDAR image of Ffridd Cae Crydd (SN 749 976) on right and Ffridd Eithaf (SN 745 977) on left

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

The Trimble GeoXH 6000 gathering data at the summit of Ffridd Cae Crydd with the summit of Ffridd Eithaf in the background


LIDAR analysis confirms Ffridd Cae Crydd as higher than Ffridd Eithaf, therefore their respective bylchau are swapped and as the summit of both hills have now been surveyed with the Trimble GeoXH 6000 it is this result that is being prioritised for listing purposes. 

The Trimble GeoXH 6000 survey result for each summit is given below:

 

Ffridd Cae Crydd:  272.289m at SN 74910 97692 

Ffridd Eithaf:  272.175m at SN 74578 97750 

 

Therefore, the confirmation of the reclassification of this hill from Welsh Sub-P15 status is due to LIDAR analysis and a subsequent Trimble GeoXH 6000 survey, resulting in a 272.3m summit height and a 232.8m bwlch height, with these values giving this hill 39.4m of drop, which is sufficient for it to be classified as a 200m Twmpau. 

 

The full details for the hill are: 

Group:  Pumlumon 

Name:  Ffridd Cae Crydd 

OS 1:50,000 map:  135

Summit Height:  272.3m (converted to OSGM15, Trimble GeoXH 6000)

Summit Grid Reference:  SN 74910 97692 (Trimble GeoXH 6000) 

Bwlch Height:  232.8m (LIDAR) 

Bwlch Grid Reference:  SN 75107 97628 (LIDAR) 

Drop:  39.4m (Trimble GeoXH 6000 summit and LIDAR bwlch) 

 

Myrddyn Phillips (October 2021)




Mapping Mountains - Hill Reclassifications - The Welsh P15s

Melin Llanddyfnan (SH 483 786) – Welsh Sub-P15 addition (20th reclassification)

Significant Name Changes post for Melin Llanddyfnan


There has been an addition to the list of The Welsh P15s, with the summit height, bwlch height and their locations, the drop and status of the hill derived from LIDAR analysis conducted by Myrddyn Phillips. 

LIDAR image of Melin Llanddyfnan (SH 483 786)

The criteria for the list that this addition applies to are: 

The Welsh P15s – Welsh hills with 15m minimum drop, irrespective of their height, with an accompanying sub list entitled the Welsh Sub-P15s, with the criteria for this sub category being all Welsh hills with 14m or more and below 15m of drop.  The list is authored by Myrddyn Phillips, with the Introduction to the list appearing on Mapping Mountains on the 10th May 2019. 

The Welsh P15s by Myrddyn Phillips

The name the hill is listed by is Melin Llanddyfnan and this was derived from online sources in combination with detail on the Tithe map, and it is adjoined to the Ynys Môn group of hills, which are situated in the north-western part of North Wales (Region A, Sub-Region A1), and it is positioned with the coast to its north-east, a minor road to its immediate north-west and south, the B5110 road farther to its north-west and the B5109 road to its south-east, and has the town of Llangefni towards the south-west. 

When the listing that became known as The Welsh P15s was being compiled, this hill was not included in the P14 sub list and was listed with an estimated c 13m of drop, based on an estimated c 86m summit height and an estimated c 73m bwlch height, with both heights based on interpolation of 5m contouring that appear on the Ordnance Survey 1:25,000 Explorer map. 

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

Therefore, the addition of this hill to Welsh Sub-P15 status is due to LIDAR analysis, resulting in an 87.2m summit height and a 72.2m bwlch height, with these values giving this hill 14.9m 0f drop, which is sufficient for it to be classified as a Welsh Sub-P15. 

 

The full details for the hill are: 

Group:  Ynys Môn 

Name:  Melin Llanddyfnan 

OS 1:50,000 map:  114, 115

Summit Height:  87.2m (LIDAR)                                                           

Summit Grid Reference:  SH 48371 78617 (LIDAR) 

Bwlch Height:  72.2m (LIDAR) 

Bwlch Grid Reference:  SH 48391 79121 (LIDAR) 

Drop:  14.9m (LIDAR) 

 

Myrddyn Phillips (October 2021)

 



Mapping Mountains - Hill Reclassifications - The Welsh P15s

Tredda Ffridd Fawr (SH 384 716) – Welsh Sub-P15 deletion (19th reclassification)

Significant Name Changes post for Tredda Ffridd Fawr


There has been a deletion to the list of The Welsh P15s, with the summit height, bwlch height and their locations, the drop and status of the hill derived from LIDAR analysis conducted by Myrddyn Phillips. 

LIDAR image of Tredda Ffridd Fawr (SH 384 716)

The criteria for the list that this deletion applies to are: 

The Welsh P15s – Welsh hills with 15m minimum drop, irrespective of their height, with an accompanying sub list entitled the Welsh Sub-P15s, with the criteria for this sub category being all Welsh hills with 14m or more and below 15m of drop.  The list is authored by Myrddyn Phillips, with the Introduction to the list appearing on Mapping Mountains on the 10th May 2019. 

The Welsh P15s by Myrddyn Phillips

The name the hill is listed by is Tredda Ffridd Fawr and this was derived from the Tithe map, and it is adjoined to the Ynys Môn group of hills, which are situated in the north-western part of North Wales (Region A, Sub-Region A1), and it is positioned with the coast to its south-west and is encircled by minor roads, the A4080 road farther to its south-west and the B4422 road farther to its south-east, and has the village of Aberffraw towards the south-west. 

When the listing that became known as The Welsh P15s was being compiled, this hill was included in the P14 sub list with an estimated c 14m of drop, based on the 48m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and an estimated c 34m bwlch height, based on interpolation of 5m contouring between 30m – 35m. 

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

Therefore, the deletion of this hill from Welsh Sub-P15 status is due to LIDAR analysis, resulting in a 48.5m summit height and a 35.7m bwlch height, with these values giving this hill 12.8m 0f drop, which is insufficient for it to be classified as a Welsh Sub-P15. 

 

The full details for the hill are: 

Group:  Ynys Môn 

Name:  Tredda Ffridd Fawr 

OS 1:50,000 map:  114

Summit Height:  48.5m (LIDAR)                                                           

Summit Grid Reference:  SH 38448 71642 & SH 38445 71640 (LIDAR) 

Bwlch Height:  35.7m (LIDAR) 

Bwlch Grid Reference:  SH 38806 71755 & SH 38805 71754 (LIDAR) 

Drop:  12.8m (LIDAR) 

 

Myrddyn Phillips (October 2021)

 



Mapping Mountains - Hill Reclassifications - The Welsh P15s

Pt. 52.0m (SH 341 800) – Welsh Sub-P15 deletion (18th reclassification)


There has been a deletion to the list of The Welsh P15s, with the summit height, bwlch height and their locations, the drop and status of the hill derived from LIDAR analysis conducted by Myrddyn Phillips. 

LIDAR image of Pt. 52.0m (SH 341 800)

The criteria for the list that this deletion applies to are: 

The Welsh P15s – Welsh hills with 15m minimum drop, irrespective of their height, with an accompanying sub list entitled the Welsh Sub-P15s, with the criteria for this sub category being all Welsh hills with 14m or more and below 15m of drop.  The list is authored by Myrddyn Phillips, with the Introduction to the list appearing on Mapping Mountains on the 10th May 2019. 

The Welsh P15s by Myrddyn Phillips

The hill is being listed by the point (Pt. 52.0m) notation as an appropriate name for it either through local enquiry and / or historic research has not been found by the author, and it is adjoined to the Ynys Môn group of hills, which are situated in the north-western part of North Wales (Region A, Sub-Region A1), and it is positioned with the coast to its west, a minor road beside its summit, the B5109 road to its north and the A5 and A55 roads to its south, and has the village of Bodedern towards the west. 

When the listing that became known as The Welsh P15s was being compiled, this hill was included in the P14 sub list with 14m of drop, based on the 52m summit spot height that appeared on the Ordnance Survey Vector Map Local hosted on the Geograph website and which was entitled the Interactive Coverage Map, and the 38m bwlch spot height that appears on the Ordnance Survey 1:25,000 Explorer map. 

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

Therefore, the deletion of this hill from Welsh Sub-P15 status is due to LIDAR analysis, resulting in a 52.0m summit height and a 38.45m bwlch height, with these values giving this hill 13.6m 0f drop, which is insufficient for it to be classified as a Welsh Sub-P15. 

 

The full details for the hill are: 

Group:  Ynys Môn 

Name:  Pt. 52.0m 

OS 1:50,000 map:  114

Summit Height:  52.0m (LIDAR)                                                           

Summit Grid Reference:  SH 34189 80031 (LIDAR) 

Bwlch Height:  38.45m (LIDAR) 

Bwlch Grid Reference:  SH 34589 80216 (LIDAR) 

Drop:  13.6m (LIDAR) 

 

Myrddyn Phillips (October 2021)

 

 

 

Mapping Mountains - Hill Reclassifications - The Welsh P15s

Carnau (SH 303 764) – Welsh Sub-P15 deletion (17th reclassification)

Significant Name Changes post for Carnau


There has been a deletion to the list of The Welsh P15s, with the summit height, bwlch height and their locations, the drop and status of the hill derived from LIDAR analysis conducted by Myrddyn Phillips. 

LIDAR image of Carnau (SH 303 764)

The criteria for the list that this deletion applies to are: 

The Welsh P15s – Welsh hills with 15m minimum drop, irrespective of their height, with an accompanying sub list entitled the Welsh Sub-P15s, with the criteria for this sub category being all Welsh hills with 14m or more and below 15m of drop.  The list is authored by Myrddyn Phillips, with the Introduction to the list appearing on Mapping Mountains on the 10th May 2019. 

The Welsh P15s by Myrddyn Phillips

The name the hill is listed by is Carnau and this was derived from the Tithe map, and it is adjoined to the Ynys Môn group of hills, which are situated in the north-western part of North Wales (Region A, Sub-Region A1), and it is positioned with the coast to its west, minor roads to its north, west and east and the A5 and A55 roads farther to its north-east, and has the village of Llanfair-yn-neubwll towards the north. 

When the listing that became known as The Welsh P15s was being compiled, this hill was included in the P14 sub list with an estimated c 14m of drop, based on the 22m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and an estimated c 8m bwlch height, based on interpolation of 5m contouring between 5m – 10m that appears on the Ordnance Survey 1:25,000 Explorer map. 

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

Therefore, the deletion of this hill from Welsh Sub-P15 status is due to LIDAR analysis, resulting in a 22.1m summit height and a 9.8m bwlch height, with these values giving this hill 12.4m 0f drop, which is insufficient for it to be classified as a Welsh Sub-P15. 

 

The full details for the hill are: 

Group:  Ynys Môn 

Name:  Carnau 

OS 1:50,000 map:  114

Summit Height:  22.1m (LIDAR)                                                           

Summit Grid Reference:  SH 30392 76417 (LIDAR) 

Bwlch Height:  9.8m (LIDAR) 

Bwlch Grid Reference:  SH 30351 76179 & SH 30350 76178 (LIDAR) 

Drop:  12.4m (LIDAR) 

 

Myrddyn Phillips (September 2021)

 

 


Mapping Mountains - Hill Reclassifications - The Welsh P15s

Plas (SH 350 772) – Welsh P15 reclassified to Welsh Sub-P15 (16th reclassification)

Significant Name Changes post for Plas

 

There has been a reclassification to the list of The Welsh P15s, with the summit height, bwlch height and their locations, the drop and status of the hill derived from LIDAR analysis conducted by Myrddyn Phillips. 

LIDAR image of Plas (SH 350 772)

The criteria for the list that this reclassification applies to are: 

The Welsh P15s – Welsh hills with 15m minimum drop, irrespective of their height, with an accompanying sub list entitled the Welsh Sub-P15s, with the criteria for this sub category being all Welsh hills with 14m or more and below 15m of drop.  The list is authored by Myrddyn Phillips, with the Introduction to the list appearing on Mapping Mountains on the 10th May 2019. 

The Welsh P15s by Myrddyn Phillips

The name the hill is listed by is Plas and this was derived from the Tithe map and it is adjoined to the Ynys Môn group of hills, which are situated in the north-western part of North Wales (Region A, Sub-Region A1), and it is positioned with the coast to its west, the A5 road to its north, a minor road to its west and the A55 road to its south, and has the village of Gwalchmai towards the east south-east. 

When the listing that became known as The Welsh P15s was being compiled, this hill was included in the main P15 list with 15m of drop, based on the 39m summit spot height and the 24m bwlch spot height that appeared on the Ordnance Survey Vector Map Local hosted on the Geograph website and which was entitled the Interactive Coverage Map. 

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

Therefore, the reclassification of this hill to Welsh Sub-P15 status is due to LIDAR analysis, resulting in a 37.4m summit height and a 22.6m bwlch height, with these values giving this hill 14.8m of drop, which is insufficient for it to be included in the main list of The Welsh P15s. 

 

The full details for the hill are: 

Group:  Ynys Môn 

Name:  Plas 

OS 1:50,000 map:  114

Summit Height:  37.4m (LIDAR)                                                           

Summit Grid Reference:  SH 35001 77280 (LIDAR) 

Bwlch Height:  22.6m (LIDAR) 

Bwlch Grid Reference:  SH 35405 77441 (LIDAR) 

Drop:  14.8m (LIDAR) 

 

Myrddyn Phillips (September 2021)




Mapping Mountains - Hill Reclassifications - The Welsh P15s

Pen yr Allt (SH 429 917) – Welsh P15 reclassified to Welsh Sub-P15 (15th reclassification)

Significant Name Changes post for Pen yr Allt

 

There has been a reclassification to the list of The Welsh P15s, with the summit height, bwlch height and their locations, the drop and status of the hill derived from LIDAR analysis conducted by Myrddyn Phillips. 

LIDAR image of Pen yr Allt (SH 429 917)

The criteria for the list that this reclassification applies to are: 

The Welsh P15s – Welsh hills with 15m minimum drop, irrespective of their height, with an accompanying sub list entitled the Welsh Sub-P15s, with the criteria for this sub category being all Welsh hills with 14m or more and below 15m of drop.  The list is authored by Myrddyn Phillips, with the Introduction to the list appearing on Mapping Mountains on the 10th May 2019. 

The Welsh P15s by Myrddyn Phillips

The name the hill is listed by is Pen yr Allt and this was derived from the Tithe map and it is adjoined to the Ynys Môn group of hills, which are situated in the north-western part of North Wales (Region A, Sub-Region A1), and it is positioned with the coast to its north, and is encircled by minor roads with the A5025 road farther to its north and the B5111 road farther to its east, and has the town of Amlwch towards the north-east. 

When the listing that became known as The Welsh P15s was being compiled, this hill was included in the main P15 list with 15m of drop, based on the 69m summit spot height that appeared on the Ordnance Survey Vector Map Local hosted on the Geograph website and which was entitled the Interactive Coverage Map and the 54m bwlch spot height that appears on the Ordnance Survey 1:25,000 Explorer map. 

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

Therefore, the reclassification of this hill to Welsh Sub-P15 status is due to LIDAR analysis, resulting in a 69.4m summit height and a 55.1m bwlch height, with these values giving this hill 14.3m of drop, which is insufficient for it to be included in the main list of The Welsh P15s. 

 

The full details for the hill are: 

Group:  Ynys Môn 

Name:  Pen yr Allt 

OS 1:50,000 map:  114

Summit Height:  69.4m (LIDAR)                                                           

Summit Grid Reference:  SH 42925 91717 (LIDAR) 

Bwlch Height:  55.1m (LIDAR) 

Bwlch Grid Reference:  SH 43244 91030 (LIDAR) 

Drop:  14.3m (LIDAR) 

 

Myrddyn Phillips (September 2021)

 



Mapping Mountains - Hill Reclassifications - The Welsh P15s

Mynydd Mechell (SH 353 899) – Welsh Sub-P15 deletion (14th reclassification)


There has been a deletion to the list of The Welsh P15s, with the summit height, bwlch height and their locations, the drop and status of the hill derived from detail on contemporary maps produced from Ordnance Survey data and LIDAR analysis conducted by Myrddyn Phillips. 

LIDAR image of Mynydd Mechell (SH 353 899)

The criteria for the list that this deletion applies to are: 

The Welsh P15s – Welsh hills with 15m minimum drop, irrespective of their height, with an accompanying sub list entitled the Welsh Sub-P15s, with the criteria for this sub category being all Welsh hills with 14m or more and below 15m of drop.  The list is authored by Myrddyn Phillips, with the Introduction to the list appearing on Mapping Mountains on the 10th May 2019. 

The Welsh P15s by Myrddyn Phillips

The name the hill is listed by is Mynydd Mechell and it is adjoined to the Ynys Môn group of hills, which are situated in the north-western part of North Wales (Region A, Sub-Region A1), and it is positioned with the coast to its north and has minor roads to its north, south and east and the A5025 road to its west, and has the village of Llanfechell towards the north-east. 

When the listing that became known as The Welsh P15s was being compiled, this hill was included in the P14 sub list with an estimated c 14m of drop, based on the 82m summit spot height that appeared on the Ordnance Survey Vector Map Local hosted on the Geograph website and which was entitled the Interactive Coverage Map and an estimated c 68m bwlch height, based on interpolation of 5m contouring between 65m – 70m that appears on the Ordnance Survey 1:25,000 Explorer map. 

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

Therefore, the deletion of this hill from Welsh Sub-P15 status is due to detail on contemporary maps produced from Ordnance Survey data and LIDAR analysis, resulting in an 80.3m summit height and an estimated c 68m bwlch height, with these values giving this hill an estimated c 12m 0f drop, which is insufficient for it to be classified as a Welsh Sub-P15. 

 

The full details for the hill are: 

Group:  Ynys Môn 

Name:  Mynydd Mechell 

OS 1:50,000 map:  114

Summit Height:  80.3m (LIDAR)                                                           

Summit Grid Reference:  SH 35360 89987 (LIDAR) 

Bwlch Height:  c 68m (interpolation) 

Bwlch Grid Reference:  SH 35255 89745 & SH 35362 89116 & SH 35283 89513 (interpolation) 

Drop:  c 12m (LIDAR summit and interpolated bwlch) 

 

Myrddyn Phillips (September 2021)




Mapping Mountains - Hill Reclassifications - The Welsh P15s

Bod Orsedd (SH 364 916) – Welsh P15 reclassified to Welsh Sub-P15 (13th reclassification)

Significant Name Changes post for Bod Orsedd

 

There has been a reclassification to the list of The Welsh P15s, with the summit height, bwlch height and their locations, the drop and status of the hill derived from LIDAR analysis conducted by Myrddyn Phillips. 

LIDAR image of Bod Orsedd (SH 364 916)

The criteria for the list that this reclassification applies to are: 

The Welsh P15s – Welsh hills with 15m minimum drop, irrespective of their height, with an accompanying sub list entitled the Welsh Sub-P15s, with the criteria for this sub category being all Welsh hills with 14m or more and below 15m of drop.  The list is authored by Myrddyn Phillips, with the Introduction to the list appearing on Mapping Mountains on the 10th May 2019. 

The Welsh P15s by Myrddyn Phillips

The name the hill is listed by is Bod Orsedd and this was derived from the Tithe map and it is adjoined to the Ynys Môn group of hills, which are situated in the north-western part of North Wales (Region A, Sub-Region A1), and it is positioned with the coast to its north, the A5025 road to its west and minor roads to its south and east, and has the village of Cemaes towards the north north-east. 

When the listing that became known as The Welsh P15s was being compiled, this hill was included in the main P15 list with an estimated c 16m of drop, based on the 44m summit spot height that appeared on the Ordnance Survey Vector Map Local hosted on the Geograph website and which was entitled the Interactive Coverage Map and an estimated c 28m bwlch height based on interpolation of 5m contouring between 25m – 30m that appears on the Ordnance Survey 1:25,000 Explorer map. 

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

Therefore, the reclassification of this hill to Welsh Sub-P15 status is due to LIDAR analysis, resulting in a 43.3m summit height and a 28.8m bwlch height, with these values giving this hill 14.5m of drop, which is insufficient for it to be included in the main list of The Welsh P15s. 

 

The full details for the hill are: 

Group:  Ynys Môn 

Name:  Bod Orsedd 

OS 1:50,000 map:  114

Summit Height:  43.3m (LIDAR)                                                           

Summit Grid Reference:  SH 36400 91688 (LIDAR) 

Bwlch Height:  28.8m (LIDAR) 

Bwlch Grid Reference:  SH 36530 92019 & SH 36531 92017 (LIDAR) 

Drop:  14.5m (LIDAR) 

 

Myrddyn Phillips (August 2021)




Mapping Mountains - Hill Reclassifications - The Welsh P15s

Nant y Frân (SH 389 923) – Welsh P15 reclassified to Welsh Sub-P15 (12th reclassification)

Significant Name Changes post for Nant y Frân

 

There has been a reclassification to the list of The Welsh P15s, with the summit height, bwlch height and their locations, the drop and status of the hill derived from LIDAR analysis conducted by Myrddyn Phillips. 

LIDAR image of Nant y Frân (SH 389 923)

The criteria for the list that this reclassification applies to are: 

The Welsh P15s – Welsh hills with 15m minimum drop, irrespective of their height, with an accompanying sub list entitled the Welsh Sub-P15s, with the criteria for this sub category being all Welsh hills with 14m or more and below 15m of drop.  The list is authored by Myrddyn Phillips, with the Introduction to the list appearing on Mapping Mountains on the 10th May 2019. 

The Welsh P15s by Myrddyn Phillips

The name the hill is listed by is Nant y Frân and this was derived from the Tithe map and it is adjoined to the Ynys Môn group of hills, which are situated in the north-western part of North Wales (Region A, Sub-Region A1), and it is positioned with the coast and the A5025 road to its north, minor roads to its west, south and east, and has the village of Cemaes towards the west north-west. 

When the listing that became known as The Welsh P15s was being compiled, this hill was included in the main P15 list with 15m of drop, based on the 49m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and the 34m bwlch spot height that appeared on the Ordnance Survey Vector Map Local hosted on the Geograph website and which was entitled the Interactive Coverage Map. 

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

Therefore, the reclassification of this hill to Welsh Sub-P15 status is due to LIDAR analysis, resulting in a 49.4m summit height and a 34.7m bwlch height, with these values giving this hill 14.7m of drop, which is insufficient for it to be included in the main list of The Welsh P15s. 

 

The full details for the hill are: 

Group:  Ynys Môn 

Name:  Nant y Frân 

OS 1:50,000 map:  114

Summit Height:  49.4m (LIDAR)                                                           

Summit Grid Reference:  SH 38928 92356 (LIDAR) 

Bwlch Height:  34.7m (LIDAR) 

Bwlch Grid Reference:  SH 38859 92572 (LIDAR) 

Drop:  14.7m (LIDAR) 

 

Myrddyn Phillips (July 2021)




Mapping Mountains - Hill Reclassifications - The Welsh P15s

Llanlleiana Park (SH 386 946) – Welsh P15 reclassified to Welsh Sub-P15 (11th reclassification)

Significant Height Revisions post for Llanlleiana Park

Significant Name Changes post for Llanlleiana Park


There has been a reclassification to the list of The Welsh P15s, with the summit height, bwlch height and their locations, the drop and status of the hill derived from detail on contemporary maps produced from Ordnance Survey data. 

The criteria for the list that this reclassification applies to are: 

The Welsh P15s – Welsh hills with 15m minimum drop, irrespective of their height, with an accompanying sub list entitled the Welsh Sub-P15s, with the criteria for this sub category being all Welsh hills with 14m or more and below 15m of drop.  The list is authored by Myrddyn Phillips, with the Introduction to the list appearing on Mapping Mountains on the 10th May 2019. 

The Welsh P15s by Myrddyn Phillips

The name the hill is listed by is Llanlleiana Park and this was derived from the Tithe map and it is adjoined to the Ynys Môn group of hills, which are situated in the north-western part of North Wales (Region A, Sub-Region A1), and it is positioned with the coast to its north, a minor road and the A5025 road farther to its south, and has the village of Cemaes towards the south-west. 

When the listing that became known as The Welsh P15s was being compiled, this hill was included in the main P15 list with an estimated c 16m of drop, based on the 44m summit spot height that appeared on the Ordnance Survey Vector Map Local hosted on the Geograph website and which was entitled the Interactive Coverage Map and an estimated c 28m bwlch height based on interpolation of 5m contouring between 25m – 30m that appear on the Ordnance Survey 1:25,000 Explorer map. 

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

The details for this hill have subsequently been re-assessed against the current Ordnance Survey interactive map hosted on the Geograph website which gives a 46m summit spot height, and current 5m contouring at the bwlch which is between 30m – 35m and estimated as c 32m, with these values giving this hill an estimated c 14m of drop. 

Extract from the Ordnance Survey interactive mapping hosted on the Geograph website

Therefore, the reclassification of this hill to Welsh Sub-P15 status is due to detail on contemporary maps produced from Ordnance Survey data, resulting in a 46m summit height and an estimated c 32m bwlch height, with these values giving this hill an estimated c 14m of drop, which is insufficient for it to be included in the main list of The Welsh P15s. 

 

The full details for the hill are: 

Group:  Ynys Môn 

Name:  Llanlleiana Park 

OS 1:50,000 map:  114

Summit Height:  46m (spot height)                                                           

Summit Grid Reference:  SH 38614 94695 (spot height) 

Bwlch Height:  c 32m (interpolation) 

Bwlch Grid Reference:  SH 38606 94628 (interpolation) 

Drop:  c 14m (spot height summit and interpolated bwlch) 

 

Myrddyn Phillips (July 2021)




Mapping Mountains - Hill Reclassifications - The Welsh P15s

Mynydd Madyn (SH 454 933) – Welsh Sub-P15 deletion (10th reclassification)

Significant Name Changes post for Mynydd Madyn


There has been a deletion to the list of The Welsh P15s, with the summit height, bwlch height and their locations, the drop and status of the hill derived from LIDAR analysis conducted by Myrddyn Phillips. 

LIDAR image of Mynydd Madyn (SH 454 933)

The criteria for the list that this deletion applies to are: 

The Welsh P15s – Welsh hills with 15m minimum drop, irrespective of their height, with an accompanying sub list entitled the Welsh Sub-P15s, with the criteria for this sub category being all Welsh hills with 14m or more and below 15m of drop.  The list is authored by Myrddyn Phillips, with the Introduction to the list appearing on Mapping Mountains on the 10th May 2019. 

The Welsh P15s by Myrddyn Phillips

The name the hill is listed by is Mynydd Madyn and this was derived from the Tithe map and it is adjoined to the Ynys Môn group of hills, which are situated in the north-western part of North Wales (Region A, Sub-Region A1), and it is positioned with the coast to its north and a minor road to its south, and has the town of Amlwch towards the immediate west. 

When the listing that became known as The Welsh P15s was being compiled, this hill was included in the P14 sub list with an estimated c 14m of drop, based on the 42m summit spot height that appeared on the Ordnance Survey Vector Map Local hosted on the Geograph website and which was entitled the Interactive Coverage Map and an estimated c 28m bwlch height based on interpolation of 5m contouring between 25m – 30m that appears on the Ordnance Survey 1:25,000 Explorer map. 

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

Therefore, the deletion of this hill from Welsh Sub-P15 status is due to LIDAR analysis, resulting in a 40.9m summit height and a 27.6m bwlch height, with these values giving this hill 13.2m of drop, which is insufficient for it to be classified as a Welsh Sub-P15. 

 

The full details for the hill are: 

Group:  Ynys Môn 

Name:  Mynydd Madyn 

OS 1:50,000 map:  114

Summit Height:  40.9m (LIDAR)                                                           

Summit Grid Reference:  SH 45430 93304 (LIDAR) 

Bwlch Height:  27.6m (LIDAR) 

Bwlch Grid Reference:  SH 45414 93172 (LIDAR) 

Drop:  13.2m (LIDAR) 

 

Myrddyn Phillips (July 2021)




Mapping Mountains - Hill Reclassifications - The Welsh P15s

Bodlasan Fawr (SH 300 825) – Welsh P15 deletion (9th reclassification)  

Significant Name Changes post for Bodlasan Fawr


There has been a deletion to the list of The Welsh P15s, with the summit height, bwlch height and their locations, the drop and status of the hill derived from LIDAR analysis conducted by Myrddyn Phillips. 

LIDAR image of Bodlasan Fawr (SH 300 825)

The criteria for the list that this deletion applies to are: 

The Welsh P15s – Welsh hills with 15m minimum drop, irrespective of their height, with an accompanying sub list entitled the Welsh Sub-P15s, with the criteria for this sub category being all Welsh hills with 14m or more and below 15m of drop.  The list is authored by Myrddyn Phillips, with the Introduction to the list appearing on Mapping Mountains on the 10th May 2019. 

The Welsh P15s by Myrddyn Phillips

The name the hill is listed by is Bodlasan Fawr and this was derived from the Tithe map and it is adjoined to the Ynys Môn group of hills, which are situated in the north-western part of North Wales (Region A, Sub-Region A1), and it is positioned with the coast to its west, minor roads to its north and south and the A5025 road to its east, and has the village of Llanfachreth towards the east. 

When the listing that became known as The Welsh P15s was being compiled, this hill was included in the main P15 list with an estimated c 15m of drop, based on the 23m summit spot height that appeared on the Ordnance Survey Vector Map Local hosted on the Geograph website and which was entitled the Interactive Coverage Map and an estimated c 8m bwlch height, based on interpolation of 5m contouring between 5m – 10m that appears on the Ordnance Survey 1:25,000 Explorer map. 

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

Therefore, the deletion of this hill from Welsh P15 status is due to LIDAR analysis, resulting in a 21.9m summit height and an 8.1m bwlch height, with these values giving this hill 13.8m of drop, which is insufficient for it to be classified as a Welsh P15. 

 

The full details for the hill are: 

Group:  Ynys Môn 

Name:  Bodlasan Fawr 

OS 1:50,000 map:  114

Summit Height:  21.9m (LIDAR)                                                           

Summit Grid Reference:  SH 30056 82550 (LIDAR) 

Bwlch Height:  8.1m (LIDAR) 

Bwlch Grid Reference:  SH 30641 82944 (LIDAR) 

Drop:  13.8m (LIDAR) 

 

Myrddyn Phillips (June 2021)




Mapping Mountains - Hill Reclassifications - The Welsh P15s

Wylfa (SH 353 939) – Welsh P15 reclassified to Welsh Sub-P15 (8th reclassification)

Significant Name Changes post for Wylfa


There has been a reclassification to the list of The Welsh P15s, with the summit height, bwlch height and their locations, the drop and status of the hill confirmed by LIDAR analysis conducted by Myrddyn Phillips. 

LIDAR image of Wylfa (SH 353 939)

The criteria for the list that this reclassification applies to are: 

The Welsh P15s – Welsh hills with 15m minimum drop, irrespective of their height, with an accompanying sub list entitled the Welsh Sub-P15s, with the criteria for this sub category being all Welsh hills with 14m or more and below 15m of drop.  The list is authored by Myrddyn Phillips, with the Introduction to the list appearing on Mapping Mountains on the 10th May 2019. 

The Welsh P15s by Myrddyn Phillips

The name the hill is listed by is Wylfa and this was derived from the Tithe map and it is adjoined to the Ynys Môn group of hills, which are situated in the north-western part of North Wales (Region A, Sub-Region A1), and it is positioned with the coast to its north, west and east and has a minor road and the A5025 road farther afield to its south-east, and has the village of Cemaes towards the east south-east. 

When the listing that became known as The Welsh P15s was being compiled, this hill was included in the main P15 list with an estimated c 15m of drop, based on the 37m summit spot height that appeared on the Ordnance Survey Vector Map Local hosted on the Geograph website and which was entitled the Interactive Coverage Map and an estimated c 22m bwlch height based on interpolation of 5m contouring between 20m – 25m that appear on the Ordnance Survey 1:25,000 Explorer map. 

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

Therefore, the reclassification of this hill to Welsh Sub-P15 status is due to LIDAR analysis, resulting in a 38.1m summit height and a 23.9m bwlch height, with these values giving this hill 14.2m of drop, which is insufficient for it to be included in the main list of The Welsh P15s. 

 

The full details for the hill are: 

Group:  Ynys Môn 

Name:  Wylfa 

OS 1:50,000 map:  114

Summit Height:  38.1m (LIDAR)                                                           

Summit Grid Reference:  SH 35376 93925 (LIDAR) 

Bwlch Height:  23.9m (LIDAR) 

Bwlch Grid Reference:  SH 35428 93863 (LIDAR) 

Drop:  14.2m (LIDAR) 

 

Myrddyn Phillips (June 2021)

 

 


Mapping Mountains - Hill Reclassifications - The Welsh P15s

Felin Wynt (SH 608 811) – Welsh Sub-P15 addition (7th reclassification)

Significant Name Changes post for Felin Wynt


There has been an addition to the list of The Welsh P15s, with the summit height, bwlch height and their locations, the drop and status of the hill derived from detail on contemporary maps produced from Ordnance Survey data and LIDAR analysis conducted by Myrddyn Phillips. 

LIDAR image of Felin Wynt (SH 608 811)

The criteria for the list that this addition applies to are: 

The Welsh P15s – Welsh hills with 15m minimum drop, irrespective of their height, with an accompanying sub list entitled the Welsh Sub-P15s, with the criteria for this sub category being all Welsh hills with 14m or more and below 15m of drop.  The list is authored by Myrddyn Phillips, with the Introduction to the list appearing on Mapping Mountains on the 10th May 2019. 

The Welsh P15s by Myrddyn Phillips

The name the hill is listed by is Felin Wynt and this was derived from the Tithe map and it is adjoined to the Ynys Môn group of hills, which are situated in the north-western part of North Wales (Region A, Sub-Region A1), and it is positioned with the coast to its north and with minor roads to its west, south and east, and has the small community of Glan-yr-afon towards the west south-west. 

When the listing that became known as The Welsh P15s was being compiled, this hill was not included in the P14 sub list and was listed with 13m of drop, based on the 94m summit and 81m bwlch spot heights that appeared on the Ordnance Survey Vector Map Local hosted on the Geograph website and which was entitled the Interactive Coverage Map. 

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

Therefore, the addition of this hill to Welsh Sub-P15 status is due to LIDAR analysis and detail on contemporary maps produced from Ordnance Survey data, resulting in a 95.2m summit height and an 81m bwlch height with these values giving this hill 14m of drop, which is sufficient for it to be classified as a Welsh Sub-P15. 

 

The full details for the hill are: 

Group:  Ynys Môn 

Name:  Felin Wynt 

OS 1:50,000 map:  114, 115

Summit Height:  95.2m (LIDAR)                                                           

Summit Grid Reference:  SH 60835 81107 (LIDAR) 

Bwlch Height:  81m (spot height) 

Bwlch Grid Reference:  SH 61129 80980 (spot height) 

Drop:  14m (LIDAR summit and spot height bwlch) 

 

Myrddyn Phillips (June 2021)

 



Mapping Mountains - Hill Reclassifications - The Welsh P15s

Parc y Ffynnon (SH 634 808) – Welsh Sub-P15 reclassified to Welsh P15 (6th reclassification)

Significant Height Revisions post for Parc y Ffynnon


There has been a reclassification to the list of The Welsh P15s, with the summit height, bwlch height and their locations, the drop and status of the hill derived from LIDAR analysis conducted by Myrddyn Phillips. 

LIDAR image of Parc y Ffynnon (SH 634 808)

The criteria for the list that this reclassification applies to are: 

The Welsh P15s – Welsh hills with 15m minimum drop, irrespective of their height, with an accompanying sub list entitled the Welsh Sub-P15s, with the criteria for this sub category being all Welsh hills with 14m or more and below 15m of drop.  The list is authored by Myrddyn Phillips, with the Introduction to the list appearing on Mapping Mountains on the 10th May 2019. 

The Welsh P15s by Myrddyn Phillips

The name the hill is listed by is Parc y Ffynnon and it is adjoined to the Ynys Môn group of hills, which are situated in the north-western part of North Wales (Region A, Sub-Region A1), and it is positioned with the coast to its north, south and east and a minor road to its immediate west, and has the village of Llangoed towards the south-west. 

When the listing that became known as The Welsh P15s was being compiled, this hill was included in the P14 sub list with 14m of drop, based on the 59m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and the 44m bwlch spot height that appeared on the Ordnance Survey Vector Map Local hosted on the Geograph website and which was entitled the Interactive Coverage Map. 

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

Therefore, the reclassification of this hill from Welsh Sub-P15 status is due to LIDAR analysis, resulting in a 60.6m summit height and a 44.8m bwlch height, with these values giving this hill 15.8m of drop, which is sufficient for it to be included in the main list of The Welsh P15s. 

 

The full details for the hill are: 

Group:  Ynys Môn 

Name:  Parc y Ffynnon 

OS 1:50,000 map:  114, 115

Summit Height:  60.6m (LIDAR)                                                           

Summit Grid Reference:  SH 63430 80880 (LIDAR) 

Bwlch Height:  44.8m (LIDAR) 

Bwlch Grid Reference:  SH 63199 81029 (LIDAR) 

Drop:  15.8m (LIDAR) 

 

Myrddyn Phillips (May 2021)




Mapping Mountains - Hill Reclassifications - The Welsh P15s

Bryn Llwyd (SH 396 644) – Welsh P15 reclassified to Welsh Sub-P15 (5th reclassification)

Significant Height Revisions post for Bryn Llwyd


There has been a reclassification to the list of The Welsh P15s, with the summit height, bwlch height and their locations, the drop and status of the hill derived from LIDAR analysis conducted by Myrddyn Phillips. 

LIDAR image of Bryn Llwyd (SH 396 644)

The criteria for the list that this reclassification applies to are: 

The Welsh P15s – Welsh hills with 15m minimum drop, irrespective of their height, with an accompanying sub list entitled the Welsh Sub-P15s, with the criteria for this sub category being all Welsh hills with 14m or more and below 15m of drop.  The list is authored by Myrddyn Phillips, with the Introduction to the list appearing on Mapping Mountains on the 10th May 2019. 

The Welsh P15s by Myrddyn Phillips

The name the hill is listed by is Bryn Llwyd and it is adjoined to the Ynys Môn group of hills, which are situated in the north-western part of North Wales (Region A, Sub-Region A1), and it is encircled by the Newborough Forest, and has the coast to its south-west and the A4080 road to its north-east, and has the village of Niwbwrch (Newborough) towards the east north-east. 

When the listing that became known as The Welsh P15s was being compiled, this hill was included in the main P15 list with an estimated c 15m of drop, based on an estimated c 46m summit height and an estimated c 31m bwlch height, with both heights based on interpolation of 5m contouring that appear on the Ordnance Survey 1:25,000 Explorer map. 

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

Therefore, the reclassification of this hill to Welsh Sub-P15 status is due to LIDAR analysis, resulting in a 43.4m summit height and a 28.6m bwlch height, with these values giving this hill 14.9m of drop, which is insufficient for it to be included in the main list of The Welsh P15s. 

 

The full details for the hill are: 

Group:  Ynys Môn 

Name:  Bryn Llwyd 

OS 1:50,000 map:  114

Summit Height:  43.4m (LIDAR)                                                           

Summit Grid Reference:  SH 39665 64415 (LIDAR) 

Bwlch Height:  28.6m (LIDAR) 

Bwlch Grid Reference:  SH 39795 64510 (LIDAR) 

Drop:  14.9m (LIDAR) 

 

Myrddyn Phillips (May 2021)




Mapping Mountains - Hill Reclassifications - The Welsh P15s

Bonc (SH 539 796) – Welsh Sub-P15 deletion (4th reclassification)

Significant Name Changes post for Bonc


There has been a deletion to the list of The Welsh P15s, with the summit height, bwlch height and their locations, the drop and status of the hill derived from LIDAR analysis conducted by Myrddyn Phillips. 

LIDAR image of Bonc (SH 539 796)

The criteria for the list that this deletion applies to are: 

The Welsh P15s – Welsh hills with 15m minimum drop, irrespective of their height, with an accompanying sub list entitled the Welsh Sub-P15s, with the criteria for this sub category being all Welsh hills with 14m or more and below 15m of drop.  The list is authored by Myrddyn Phillips, with the Introduction to the list appearing on Mapping Mountains on the 10th May 2019. 

The Welsh P15s by Myrddyn Phillips

The name the hill is listed by is Bonc and this was derived from the Tithe map and it is adjoined to the Ynys Môn group of hills, which are situated in the north-western part of North Wales (Region A, Sub-Region A1), and it is positioned with the coast to its north and a minor road to its immediate north-west, and has the village of Pentraeth towards the south-west. 

When the listing that became known as The Welsh P15s was being compiled, this hill was included in the P14 sub list with an estimated c 14m of drop, based on an estimated c 32m summit height and an estimated c 18m bwlch height, with both heights based on interpolation of 5m contouring that appears on the Ordnance Survey 1:25,000 Explorer map. 

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

Therefore, the deletion of this hill from Welsh Sub-P15 status is due to LIDAR analysis, resulting in a 33.5m summit height and a 20.85m bwlch height, with these values giving this hill 12.7m of drop, which is insufficient for it to be classified as a Welsh Sub-P15. 

 

The full details for the hill are: 

Group:  Ynys Môn 

Name:  Bonc 

OS 1:50,000 map:  114, 115

Summit Height:  33.5m (LIDAR)                                                           

Summit Grid Reference:  SH 53915 79698 (LIDAR) 

Bwlch Height:  20.85m (LIDAR) 

Bwlch Grid Reference:  SH 53863 79583 & SH 53862 79582 (LIDAR) 

Drop:  12.7m (LIDAR) 

 

Myrddyn Phillips (May 2021)

 



Mapping Mountains - Hill Reclassifications - The Welsh P15s

Pt. 27.7m (SH 252 818) – Welsh Sub-P15 reclassified to Welsh P15 (3rd reclassification)


There has been a reclassification to the list of The Welsh P15s, with the summit height, bwlch height and their locations, the drop and status of the hill derived from LIDAR analysis conducted by Myrddyn Phillips. 

LIDAR image of Pt. 27.7m (SH 252 818)

The criteria for the list that this reclassification applies to are: 

The Welsh P15s – Welsh hills with 15m minimum drop, irrespective of their height, with an accompanying sub list entitled the Welsh Sub-P15s, with the criteria for this sub category being all Welsh hills with 14m or more and below 15m of drop.  The list is authored by Myrddyn Phillips, with the Introduction to the list appearing on Mapping Mountains on the 10th May 2019. 

The Welsh P15s by Myrddyn Phillips

The hill is being listed by the point (Pt. 27.7m) notation as an appropriate name for it either through local enquiry and / or historic research has not been found by the author, and it is adjoined to the Ynys Môn group of hills, which are situated in the north-western part of North Wales (Region A, Sub-Region A1), and it is positioned with a minor road to its immediate north-east and the A5 road to its immediate south-west, and has the town of Caergybi (Holyhead) surrounding it. 

When the listing that became known as The Welsh P15s was being compiled, this hill was included in the P14 sub list with an estimated c 14m of drop, based on the 26m summit spot height that appeared on the Ordnance Survey Vector Map Local hosted on the Geograph website and which was entitled the Interactive Coverage Map, and an estimated c 12m bwlch height based on interpolation of 5m contouring between 10m – 15m that appear on the Ordnance Survey 1:25,000 Explorer map. 

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

Therefore, the reclassification of this hill from Welsh Sub-P15 status is due to LIDAR analysis, resulting in a 27.7m summit height and a 12.0m bwlch height, with these values giving this hill 15.7m of drop, which is sufficient for it to be included in the main list of The Welsh P15s. 

 

The full details for the hill are: 

Group:  Ynys Môn 

Name:  Pt. 27.7m 

OS 1:50,000 map:  114

Summit Height:  27.7m (LIDAR)                                                           

Summit Grid Reference:  SH 25232 81874 (LIDAR) 

Bwlch Height:  12.0m (LIDAR) 

Bwlch Grid Reference:  SH 25327 81236 (LIDAR) 

Drop:  15.7m (LIDAR) 

 

Myrddyn Phillips (May 2021)




Mapping Mountains - Hill Reclassifications - The Welsh P15s

Pen y Castell (SH 467 852) – Welsh P15 reclassified to Welsh Sub-P15 (2nd reclassification)


There has been a reclassification to the list of The Welsh P15s, with the summit height, bwlch height and their locations, the drop and status of the hill derived from LIDAR analysis conducted by Myrddyn Phillips. 

LIDAR image of Pen y Castell (SH 467 852)

The criteria for the list that this reclassification applies to are: 

The Welsh P15s – Welsh hills with 15m minimum drop, irrespective of their height, with an accompanying sub list entitled the Welsh Sub-P15s, with the criteria for this sub category being all Welsh hills with 14m or more and below 15m of drop.  The list is authored by Myrddyn Phillips, with the Introduction to the list appearing on Mapping Mountains on the 10th May 2019. 

The Welsh P15s by Myrddyn Phillips

The name the hill is listed by is Pen y Castell and it is adjoined to the Ynys Môn group of hills, which are situated in the north-western part of North Wales (Region A, Sub-Region A1), and it is positioned with minor roads to its north, west and south and the A5025 road to its north-east, and has the village of Moelfre towards the east north-east. 

When the listing that became known as The Welsh P15s was being compiled, this hill was included in the main P15 list with an estimated c 15m of drop, based on the 169m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and an estimated c 154m bwlch height based on interpolation of 5m contouring between 150m – 155m. 

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

Therefore, the reclassification of this hill to Welsh Sub-P15 status is due to LIDAR analysis, resulting in a 168.5m summit height and a 154.0m bwlch height, with these values giving this hill 14.5m of drop, which is insufficient for it to be included in the main list of The Welsh P15s. 

 

The full details for the hill are: 

Group:  Ynys Môn 

Name:  Pen y Castell 

OS 1:50,000 map:  114

Summit Height:  168.5m (LIDAR)                                                           

Summit Grid Reference:  SH 46705 85231 (LIDAR) 

Bwlch Height:  154.0m (LIDAR) 

Bwlch Grid Reference:  SH 46753 85261 (LIDAR) 

Drop:  14.5m (LIDAR) 

 

Myrddyn Phillips (April 2021)

 

 


Mapping Mountains - Hill Reclassifications - The Welsh P15s

Tomen y Mur (SH 705 386) – Welsh Sub-P15 reclassified to Welsh P15 (1st reclassification)

Survey Post for Tomen y Mur

Significant Height Revisions post for Tomen y Mur


There has been a reclassification to the list of The Welsh P15s, with the summit height, bwlch height and their locations, the drop and status of the hill confirmed by LIDAR analysis and a subsequent Trimble GeoXH 6000 survey conducted by Myrddyn Phillips.

Tomen y Mur (SH 705 386)

The criteria for the list that this reclassification applies to are: 

The Welsh P15s – Welsh hills with 15m minimum drop, irrespective of their height, with an accompanying sub list entitled the Welsh Sub-P15s, with the criteria for this sub category being all Welsh hills with 14m or more and below 15m of drop.  The list is authored by Myrddyn Phillips, with the Introduction to the list appearing on Mapping Mountains on the 10th May 2019. 

The Welsh P15s by Myrddyn Phillips

The name the hill is listed by is Tomen y Mur, and it is adjoined to the Arenig group of hills, which are situated in the central part of North Wales (Region A, Sub-Region A3), and it is positioned with a minor road to its immediate north, the A470 road to its west and further to its north, and has the village of Trawsfynydd towards the south. 

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

When the listing that became known as The Welsh P15s was being compiled, this hill was included in the sub list with an estimated c 14m of drop, based on an estimated c 300m summit height and an estimated c 286m bwlch height, with the former based on interpolation of the uppermost 300m ring contour that appears on the WalkLakes interactive map and the latter based on interpolation of 10m contouring between 280m – 290m that appears on the Ordnance Survey 1:25,000 Explorer map and the mapping on the WalkLakes website. 

Extract from the WalkLakes website

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

LIDAR image of Tomen y Mur (SH 705 386)

The result produced by LIDAR analysis gives this hill 15.2m of drop, and as the summit has now been surveyed with the Trimble GeoXH 6000 it is this result that is being prioritised for listing purposes. 

The Trimble GeoXH 6000 gathering data at the summit of Tomen y Mur

Therefore, the reclassification of this hill from Welsh Sub-P15 status is due to LIDAR analysis and a subsequent Trimble GeoXH 6000 survey, resulting in a 303.2m summit height and a 288.1m bwlch height, with these values giving this hill 15.1m of drop, which is sufficient for it to be included in the main list of The Welsh P15s. 

 

The full details for the hill are: 

Group:  Arenig 

Name:  Tomen y Mur 

OS 1:50,000 map:  124

Summit Height:  303.2m (converted to OSGM15, Trimble GeoXH 6000)                                                          

Summit Grid Reference:  SH 70544 38679 (Trimble GeoXH 6000) 

Bwlch Height:  288.1m (LIDAR) 

Bwlch Grid Reference:  SH 70674 38754 (LIDAR) 

Drop:  15.1m (Trimble GeoXH 6000 summit and LIDAR bwlch) 

 

Myrddyn Phillips (April 2021) 

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