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

Y Dinas Ucha (SH 818 826) – Welsh P15 deletion (43rd reclassification)

Significant Name Changes post for Y Dinas Ucha

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 Y Dinas Ucha (SH 818 826)

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 10^th May 2019. 

The Welsh P15s by Myrddyn Phillips

The name the hill is now listed by is Y Dinas Ucha and this was derived from the Tithe map, and it is adjoined to the Mynydd Hiraethog group of hills, which are situated in the northern part of North Wales (Region A, Sub-Region A2), and it is positioned with the coast to its immediate north-east and the B5115 road to its south-west, and has the town of Llandudno towards the west.

When the listing that became known as The Welsh P15s was being compiled, this hill was included in the main list with an estimated c 15m of drop, based on an estimated c 42m summit height and an estimated c 27m bwlch height, with both heights based on interpolation of 5m contouring. 

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 41.8m summit height and a 28.2m bwlch height, with these values giving this hill 13.6m 0f drop, which is insufficient for it to be classified as a Welsh P15. 

 

The full details for the hill are: 

Group:  Mynydd Hiraethog 

Name:  Y Dinas Ucha 

OS 1:50,000 map:  116

Summit Height:  41.8m (LIDAR)                                                           

Summit Grid Reference:  SH 81890 82674 (LIDAR)                                                  

Bwlch Height:  28.2m (LIDAR) 

Bwlch Grid Reference:  SH 81903 82535 (LIDAR) 

Drop:  13.6m (LIDAR) 

 

Myrddyn Phillips (December 2024)

Mapping Mountains - Hill Reclassifications - The Welsh P15s

Y Faerdre (SH 784 795) – Welsh Sub-P15 deletion (42nd reclassification)

Significant Height Revisions post for Y Faerdre

Significant Name Changes post for Y Faerdre

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 Y Faerdre (SH 784 795)

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 10^th May 2019. 

The Welsh P15s by Myrddyn Phillips

The name the hill is now listed by is Y Faerdre and this was derived from the Tithe map, and it is adjoined to the Mynydd Hiraethog group of hills, which are situated in the northern part of North Wales (Region A, Sub-Region A2), and it is positioned with the A546 road to its west and the B5115 road and the A470 road to its east, and has the town of Llandudno 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 an estimated c 97m summit height and an estimated c 83m bwlch height, with both heights based on interpolation of 5m contouring. 

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 93.2m summit height and an 81.1m bwlch height, with these values giving this hill 12.2m 0f drop, which is insufficient for it to be classified as a Welsh Sub-P15. 

 

The full details for the hill are: 

Group:  Mynydd Hiraethog 

Name:  Y Faerdre 

OS 1:50,000 map:  115

Summit Height:  93.2m (LIDAR)                                                           

Summit Grid Reference:  SH 78472 79515 (LIDAR)                                                  

Bwlch Height:  81.1m (LIDAR) 

Bwlch Grid Reference:  SH 78520 79419 (LIDAR) 

Drop:  12.2m (LIDAR) 

 

Myrddyn Phillips (November 2024)

 

Mapping Mountains - Hill Reclassifications - The Welsh P15s

Bryn (SH 802 814) – Welsh Sub-P15 deletion (41st reclassification)

Significant Name Changes post for Bryn

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 Bryn (SH 802 814)

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 10^th May 2019. 

The Welsh P15s by Myrddyn Phillips

The name the hill is now listed by is Bryn and this was derived from the Tithe map, and it is adjoined to the Mynydd Hiraethog group of hills, which are situated in the northern part of North Wales (Region A, Sub-Region A2), and it is positioned with the B5115 road to its north, the A470 road to its south-west and a minor road to its south, and has the town of Llandudno towards the west north-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 122m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and an estimated c 108m bwlch height, based on interpolation of 5m contouring between 105m – 110m. 

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 121.0m summit height and a 107.2m bwlch height, with these values giving this hill 13.75m 0f drop, which is insufficient for it to be classified as a Welsh Sub-P15. 

 

The full details for the hill are: 

Group:  Mynydd Hiraethog 

Name:  Bryn 

OS 1:50,000 map:  116

Summit Height:  121.0m (LIDAR)                                                           

Summit Grid Reference:  SH 80242 81475 (LIDAR) 

Bwlch Height:  107.2m (LIDAR) 

Bwlch Grid Reference:  SH 80175 81398 (LIDAR) 

Drop:  13.75m (LIDAR) 

 

Myrddyn Phillips (October 2024)

Mapping Mountains - Hill Reclassifications - The Welsh P15s

Y Boncyn (SH 532 398) – Welsh P15 addition (40th reclassification)

Significant Height Revisions post for Y Boncyn

 

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 Y Boncyn (SH 532 398)

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 10^th May 2019. 

The Welsh P15s by Myrddyn Phillips 

The name the hill is listed by is Y Boncyn, and it is adjoined to the Moel Hebog 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 A487 road to its north and the A497 road to its south, and has the town of Porthmadog towards the east south-east.

When the listing that became known as The Welsh P15s was being compiled, this hill was not included in the main P15 or Sub P14 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

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 66.3m summit height and a 51.0m bwlch height, with these values giving this hill 15.3m 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 Hebog 

Name:  Y Boncyn 

OS 1:50,000 map:  124

Summit Height:  66.3m (LIDAR)                                                           

Summit Grid Reference:  SH 53275 39885 (LIDAR) 

Bwlch Height:  51.0m (LIDAR) 

Bwlch Grid Reference:  SH 53321 39934 (LIDAR) 

Drop:  15.3m (LIDAR) 

 

Myrddyn Phillips (September 2024)

Mapping Mountains - Hill Reclassifications - The Welsh P15s

Cae’r Lloi Mawr (SH 507 390) – Welsh P15 reclassified to Welsh Sub-P15 (39th reclassification)

Significant Name Changes post for Cae'r Lloi Mawr

 

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 Cae'r Lloi Mawr (SH 507 390)

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 10^th May 2019. 

The Welsh P15s by Myrddyn Phillips

The name the hill is listed by is Cae’r Lloi Mawr and this was derived from the Tithe map, and it is adjoined to the Moel Hebog 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 and the B4411 road to its west and the A497 road to its south, and has the town of Cricieth towards the south-west.

When the listing that became known as The Welsh P15s was being compiled, this hill was included in the main list with an estimated c 15m of drop, based on the 122m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and an estimated c 107m bwlch height, based on interpolation of 5m contouring between 105m – 110m that appeared on the OS Maps website. 

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 121.4m summit height and a 106.6m 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:  Moel Hebog 

Name:  Cae’r Lloi Mawr 

OS 1:50,000 map:  124

Summit Height:  121.4m (LIDAR)                                                           

Summit Grid Reference:  SH 50771 39098 (LIDAR) 

Bwlch Height:  106.6m (LIDAR) 

Bwlch Grid Reference:  SH 50865 39392 (LIDAR) 

Drop:  14.7m (LIDAR) 

 

Myrddyn Phillips (August 2024)

Mapping Mountains - Hill Reclassifications - The Welsh P15s

March Mynydd Ucha (SO 097 282) – Welsh Sub-P15 deletion (38th reclassification)

Significant Height Revisions post for March Mynydd Ucha

Significant Name Changes post for March Mynydd Ucha

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 March Mynydd Ucha (SO 097 282)

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 10^th May 2019. 

The Welsh P15s by Myrddyn Phillips

The name the hill is now listed by is March Mynydd Ucha and this was derived from the Tithe map, and it is adjoined to the Mynydd Epynt group of hills, which are situated in the central part of South Wales (Region B, Sub-Region B1), and it is positioned enclosed by minor roads, with the A470 road farther to its west and the A40 road farther to its south-west, and has the town of Aberhonddu (Brecon) 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 an estimated c 14m of drop, based on the 270m 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 256m bwlch height, based on interpolation of 10m contouring between 250m – 260m. 

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 271.1m summit height and a 257.4m bwlch height, with these values giving this hill 13.7m 0f drop, which is insufficient for it to be classified as a Welsh Sub-P15. 

 

The full details for the hill are: 

Group:  Mynydd Epynt 

Name:  March Mynydd Ucha 

OS 1:50,000 map:  161

Summit Height:  271.1m (LIDAR)                                                           

Summit Grid Reference:  SO 09744 28233 (LIDAR) 

Bwlch Height:  257.4m (LIDAR) 

Bwlch Grid Reference:  SO 09741 28417 (LIDAR) 

Drop:  13.7m (LIDAR) 

 

Myrddyn Phillips (July 2024)

Mapping Mountains - Hill Reclassifications - The Welsh P15s

Allt y Geifr (SN 762 284) – Welsh P15 reclassified to Welsh Sub-P15 (37th reclassification)

Significant Height Revisions post for Allt y Geifr

 

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 Allt y Geifr (SN 762 284)

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 10^th May 2019. 

The Welsh P15s by Myrddyn Phillips

The name the hill is listed by is Allt y Geifr, 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 encircled by minor roads with the A4069 road farther to its north-west and south-west, and has the village of Llangadog towards the 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 174m 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 158m bwlch height, based on interpolation of 5m contouring between 155m – 160m that appeared on the OS Maps website. 

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 171.1m summit height and a 156.9m 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:  Mynydd Du 

Name:  Allt y Geifr 

OS 1:50,000 map:  146, 160

Summit Height:  171.1m (LIDAR)                                                           

Summit Grid Reference:  SN 76221 28491 (LIDAR) 

Bwlch Height:  156.9m (LIDAR) 

Bwlch Grid Reference:  SN 76558 28873 (LIDAR) 

Drop:  14.2m (LIDAR) 

 

Myrddyn Phillips (June 2024)

Mapping Mountains - Hill Reclassifications - The Welsh P15s

Pt. 181.4m (SN 731 303) – Welsh Sub-P15 reclassified to Welsh P15 (36th 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. 181.4m (SN 731 303)

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 10^th May 2019. 

The Welsh P15s by Myrddyn Phillips

The hill is being listed by the point (Pt. 181.4m) 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 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 A4069 road to its west and a minor road to its south-east, and has the village of Llangadog 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 181m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and an estimated c 167m bwlch height, based on interpolation of 5m contouring between 165m – 170m that appeared on the OS Maps website. 

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 181.4m summit height and a 166.2m bwlch height, with these values giving this hill 15.2m 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:  Pt. 181.4m 

OS 1:50,000 map:  146, 160

Summit Height:  181.4m (LIDAR)                                                           

Summit Grid Reference:  SN 73163 30392 (LIDAR) 

Bwlch Height:  166.2m (LIDAR) 

Bwlch Grid Reference:  SN 73315 30299 (LIDAR) 

Drop:  15.2m (LIDAR) 

 

Myrddyn Phillips (June 2024)