Mapping Mountains – Summit Relocations – The Welsh P15s

 

The Welsh P15s – Summit Relocations

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 summit relocations 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 - Summit Relocations - The Welsh P15s

Y Garreg Las (SN 768 098) - 6th summit relocation

Hill Reclassifications post for Y Garreg Las

Significant Name Changes post for Y Garreg Las

 

There has been a Summit Relocation to a hill that is listed in the 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 summit relocation 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 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 positioned at SN 76897 09754 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. 

LIDAR summit image of Y Garreg Las (SN 768 098)

LIDAR analysis gives the highest ground on this hill as 158.5m positioned at SN 76803 09804, and this position comes within the parameters of the Summit Relocations used within this page heading, these parameters are:

The term Summit Relocations applies to when the high point of the hill is positioned in a different field, to a different feature such as a conifer plantation, within a different map contour, a different point where a number of potential summit positions are within close proximity, when natural ground or the natural and intact summit is confirmed compared to a higher point such as a raised field boundary or covered reservoir that is considered a relatively recent man-made construct, or a relocation of approximately 100 metres or more in distance from either the position of a map spot height or from where the summit of the hill was previously thought to exist.

Therefore, the summit height produced by LIDAR analysis is 158.5m and this is positioned at SN 76803 09804, this position is not given a spot height on the contemporary Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map, and is approximately 95 metres north-westward from where the originally listed summit is positioned. 

 

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 (New Position):  SN 76803 09804 (LIDAR) 

Bwlch Height:  141.7m (LIDAR) 

Bwlch Grid Reference:  SN 76797 09723 (LIDAR) 

Drop:  16.75m (LIDAR) 

 

Myrddyn Phillips (April 2024)

 

Mapping Mountains - Summit Relocations - The Welsh P15s

Bryn Cysegrfa (SN 643 521) - 5th summit relocation

 

There has been a Summit Relocation to a hill that is listed in the 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 Cysegrfa (SN 643 521)

The criteria for the list that this summit relocation 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 Bryn Cysegrfa, and it is adjoined to the Esgair Wen group of hills, which are situated in the central part of South Wales (Region B, Sub-Region B1), and it is positioned with the B4343 road to its north-west and minor roads to its south-west and east, and has the town of Llanbedr Pont Steffan (Lampeter) 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 20m of drop, based on the 337m summit spot height positioned at SN 64351 52092 that appears on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map and an estimated c 317m bwlch height, based on interpolation of 10m contouring between 310m – 320m. 

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.

LIDAR analysis gives the highest ground on this hill as 338.4m positioned at SN 64317 52119.  However, this is a part of a raised field boundary and protocols dictate that as this is deemed a relatively recent man-made construct such ground is discounted from the height of a hill. 

LIDAR summit image of Bryn Cysegrfa (SN 643 521)

The height produced by LIDAR analysis to the natural summit of this hill is 338.3m positioned at SN 64313 52109, and this position in relation to the raised field boundary comes within the parameters of the Summit Relocations used within this page heading, these parameters are:

The term Summit Relocations applies to when the high point of the hill is positioned in a different field, to a different feature such as a conifer plantation, within a different map contour, a different point where a number of potential summit positions are within close proximity, when natural ground or the natural and intact summit is confirmed compared to a higher point such as a raised field boundary or covered reservoir that is considered a relatively recent man-made construct, or a relocation of approximately 100 metres or more in distance from either the position of a map spot height or from where the summit of the hill was previously thought to exist.

Therefore, the summit height produced by LIDAR analysis is 338.3m and this is to the natural summit of the hill which is positioned at SN 64313 52109, this position is not given a spot height on the contemporary Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map, and is approximately 40 metres westward from where the 337m spot height appears on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map and approximately 10 metres southward from where the high point of the raised field boundary is positioned. 

 

The full details for the hill are: 

Group:  Esgair Wen 

Name:  Bryn Cysegrfa 

OS 1:50,000 map:  146

Summit Height:  338.3m (LIDAR)                                                           

Summit Grid Reference (New Position):  SN 64313 52109 (LIDAR) 

Bwlch Height:  318.8m (LIDAR) 

Bwlch Grid Reference:  SN 64689 52334 (LIDAR) 

Drop:  19.5m (LIDAR) 

 

Myrddyn Phillips (April 2023)

 

Mapping Mountains - Summit Relocations - The Welsh P15s

Tyn Ffynnon (SN 549 487) - 4th summit relocation

Hill Reclassifications post for Tyn Ffynnon

Significant Name Changes post for Tyn Ffynnon

 

There has been a Summit Relocation to a hill that is listed in the 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 summit relocation 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 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 positioned at SN 55020 48780 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.

LIDAR analysis gives the highest ground on this hill as 224.4m positioned at SN 54973 48741.  However, this is a part of a raised field boundary and protocols dictate that as this is deemed a relatively recent man-made construct such ground is discounted from the height of a hill. 

LIDAR summit image of Tyn Ffynnon (SN 549 487)

The height produced by LIDAR analysis to the natural summit of this hill is 224.3m positioned at SN 54956 48738, and this position in relation to the raised field boundary comes within the parameters of the Summit Relocations used within this page heading, these parameters are:

The term Summit Relocations applies to when the high point of the hill is positioned in a different field, to a different feature such as a conifer plantation, within a different map contour, a different point where a number of potential summit positions are within close proximity, when natural ground or the natural and intact summit is confirmed compared to a higher point such as a raised field boundary or covered reservoir that is considered a relatively recent man-made construct, or a relocation of approximately 100 metres or more in distance from either the position of a map spot height or from where the summit of the hill was previously thought to exist.

Therefore, the summit height produced by LIDAR analysis is 224.3m and this is to the natural summit of the hill which is positioned at SN 54956 48738, this position is not given a spot height on the contemporary Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map, and is approximately 70 metres south-westward from where the 224m spot height appears on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map and 17 metres westward from where the high point of the raised field boundary is positioned.

 

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 (New Position):  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 - Summit Relocations - The Welsh P15s

Maes Llwyn (SH 435 920) - 3rd summit relocation

Significant Height Revisions post for Maes Llwyn

Significant Name Changes post for Maes Llwyn

 

There has been a Summit Relocation to a hill that is listed in the 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 Maes Llwyn (SH 435 920)

The criteria for the list that this summit relocation 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 Maes Llwyn 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 B5111 road and the A5025 road farther to its north and also 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 listed with 25m of drop, based on the 77m summit spot height positioned at SH 43598 92043 on or near to a covered reservoir, that appeared on the Ordnance Survey Vector Map Local hosted on the Geograph website and which was entitled the Interactive Coverage Map and the 52m bwlch spot height that appears on the Ordnance Survey 1:50,000 Landranger 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.  

LIDAR summit image of Maes Llwyn (SH 435 920)

The height produced by LIDAR analysis to a remaining natural summit is 74.0m and is positioned at SH 43593 92022, and this comes within the parameters of the Summit Relocations used within this page heading, these parameters are: 

The term Summit Relocations applies when the hill’s high point is found to be positioned; in a different field, within a different map contour, to a different feature such as in a conifer plantation, to a different point where a number of potential summit positions are within close proximity, a relocation of approximately 100 metres or more in distance from either the position of a map spot height or from where the summit of the hill was previously thought to exist, or when natural ground or the natural and intact summit is confirmed compared to a higher point such as a raised field boundary that is judged to be a relatively recent man-made construct. 

Therefore, the summit height produced by LIDAR analysis is 74.0m and this is positioned at SH 43593 92022, this position is not given a spot height on contemporary Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer maps, and is approximately 20 metres southward from where the 77m spot height appeared on the Ordnance Survey Vector Map Local hosted on the Geograph website and which was entitled the Interactive Coverage Map. 

 

The full details for the hill are: 

Group:  Ynys Môn 

Name:  Maes Llwyn 

OS 1:50,000 map:  114

Summit Height:  74.0m (LIDAR) 

Summit Grid Reference (New Position):  SH 43593 92022 (LIDAR) 

Bwlch Height:  54.9m (LIDAR) 

Bwlch Grid Reference:  SH 43658 91747 (LIDAR) 

Drop:  19.1m (LIDAR) 

 

Myrddyn Phillips (September 2021)

 

Mapping Mountains - Summit Relocations - The Welsh P15s

Pen Ucheldref (SH 349 882) - 2nd summit relocation

Significant Height Revisions post for Pen Ucheldref

Significant Name Changes post for Pen Ucheldref

 

There has been a Summit Relocation to a hill that is listed in the 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 Pen Ucheldref (SH 349 882)

The criteria for the list that this summit relocation 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 Pen Ucheldref 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 two minor roads beside its summit and the A5025 road to its north-west, and has the village of Llanrhuddlad also towards the north-west. 

When the listing that became known as The Welsh P15s was being compiled, this hill was listed with an estimated c 23m of drop, based on an estimated c 90m summit height positioned at SH 34812 87943 and an estimated c 67m bwlch height, with both heights based on interpolation of 5m contouring that appears on the Ordnance Survey 1:25,000 Explorer map, with the 85m upper summit contour mistaken for 90m. 

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. 

The summit height produced by LIDAR analysis is 85.4m and is positioned at SH 34917 88259, and this comes within the parameters of the Summit Relocations used within this page heading, these parameters are: 

The term Summit Relocations applies when the hill’s high point is found to be positioned; in a different field, within a different map contour, to a different feature such as in a conifer plantation, to a different point where a number of potential summit positions are within close proximity, a relocation of approximately 100 metres or more in distance from either the position of a map spot height or from where the summit of the hill was previously thought to exist, or when natural ground or the natural and intact summit is confirmed compared to a higher point such as a raised field boundary that is judged to be a relatively recent man-made construct. 

Therefore, the summit height produced by LIDAR analysis is 85.4m and this is positioned at SH 34917 88259, this position is given an 85m spot height on contemporary Ordnance Survey 1:50,000 Landranger maps and an 84m spot height on contemporary Ordnance Survey 1:25,000 Explorer maps, and is approximately 320 metres northward from where the previously listed summit is positioned. 

 

The full details for the hill are: 

Group:  Ynys Môn 

Name:  Pen Ucheldref 

OS 1:50,000 map:  114

Summit Height:  85.4m (LIDAR) 

Summit Grid Reference (New Position):  SH 34917 88259 (LIDAR) 

Bwlch Height:  c 67m (interpolation) 

Bwlch Grid Reference:  SH 35183 88544 (interpolation) 

Drop:  c 18m (LIDAR summit and interpolated bwlch) 

 

Myrddyn Phillips (August 2021)

Mapping Mountains - Summit Relocations - The Welsh P15s

Cae Bryn Celli Wen (SH 513 701) - 1st summit relocation

Significant Name Changes post for Cae Bryn Celli Wen

 

There has been a Summit Relocation to a hill that is listed in the 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 Bryn Celli Wen (SH 513 701)

The criteria for the list that this summit relocation 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 Bryn Celli Wen 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 A5 and A55 roads to its north, minor roads to its north-west and south-west and the A4080 road to its east, and has the village of Llanfair Pwllgwyngyll 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 an estimated c 17m of drop, based on an estimated c 51m summit height positioned at SH 51467 70268 and a 34m bwlch height based on the spot height that appears on the Ordnance Survey 1:50,000 Landranger and 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. 

LIDAR summit image of Cae Bryn Celli Wen

The summit height produced by LIDAR analysis is 51.3m and is positioned at SH 51314 70143, and this comes within the parameters of the Summit Relocations used within this page heading, these parameters are: 

The term Summit Relocations applies when the hill’s high point is found to be positioned; in a different field, to a different feature such as in a conifer plantation, placed within a different map contour, to a different point where a number of potential summit positions are within close proximity, or when natural ground or the natural and intact summit of a hill is confirmed compared to a higher point such as a raised field boundary that is judged to be a relatively recent man-made construct, or a relocation of approximately 100 metres or more in distance from either the position of a map spot height or from where the summit of the hill was previously thought to exist. 

Therefore, the summit height produced by LIDAR analysis is 51.3m and this is positioned at SH 51314 70143, this position is not given a spot height on contemporary Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer maps, and is approximately 150 metres south-westward from where the previously listed summit is positioned. 

 

The full details for the hill are: 

Group:  Ynys Môn 

Name:  Cae Bryn Celli Wen 

OS 1:50,000 map:  114, 115

Summit Height:  51.3m (LIDAR) 

Summit Grid Reference (New Position):  SH 51314 70143 (LIDAR) 

Bwlch Height:  33.3m (LIDAR) 

Bwlch Grid Reference:  SH 51742 69854 (LIDAR) 

Drop:  18.0m (LIDAR) 

 

Myrddyn Phillips (May 2021)