The Welsh Highlands - Uchafion Cymru – Hill Reclassifications
The Welsh 500m P15s are the Welsh hills at or above 500m in height that have a minimum drop of 15m. Accompanying the main P15 list are three sub lists; these are the 500m Subs, 490m Subs and the Double Subs with their criteria detailed in the respective Change Registers which are linked in their above titles, with details to this list given in the Introduction that was published on Mapping Mountains in November 2015.
The list is co-authored by Myrddyn Phillips and Aled Williams and the posts that have appeared on Mapping Mountains detailing the additions, reclassifications and deletions to the main P15 list and the sub lists appear below presented chronologically in receding order.
Postscript: On the 7th
January 2023 it was announced that the sub hills accompanying the main listing
of the Welsh Highlands – Uchafion Cymru now take in just one category, this category
is entitled the Welsh Highland Subs. The
criteria for which are all Welsh hills at and above 500m in height with 10m or
more and below 15m of drop.
Therefore, the 490m Subs and 490m
Double Subs have been dispensed with and the criteria for the 500m Subs that
included Welsh hills with 14m or more and below 15m of drop, have been amended
to include Welsh hills with 10m or more and below 15m of drop and their title changed
to the Welsh Highland Subs.
Mapping Mountains - Hill Reclassifications - Welsh Highlands - Uchafion Cymru
Craig yr Ysfa (SH 692 636) – Welsh Highland Sub deletion (70th reclassification)
There has been a deletion to the listing of the Welsh Highlands – Uchafion Cymru, with the summit height, bwlch height and their locations, the drop and status of the hill derived from LIDAR analysis conducted by Aled Williams.
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| LIDAR image of Craig yr Ysfa (SH 692 636) |
The criteria for the list that this deletion applies to are:
Welsh Highlands – Uchafion Cymru – Welsh hills at or above 500m in height with 15m minimum drop, with an accompanying sub list entitled the Welsh Highland Subs, the criteria for which is all Welsh hills at or above 500m in height with 10m or more and below 15m of drop. This list is authored by Myrddyn Phillips and Aled Williams with the Introduction to the list published on Mapping Mountains in November 2015 and the latest update relating to the list published on Mapping Mountains in January 2023.
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| Welsh Highlands - Uchafion Cymru by Myrddyn Phillips and Aled Williams |
The name the hill is listed by is Craig yr Ysfa and it is adjoined to the Carnedd Llywelyn 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 road to its south, and has the village of Capel Curig towards the south south-east.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
When the initial P10 sub list was completed in June 2020 this hill was listed as a Welsh Highland Sub with 12.0m of drop, based on a basic levelling survey conducted by Myrddyn Phillips on the 04.06.98.
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 Highland Sub status is due to LIDAR analysis, resulting in an 864.3m summit height and an 855.0m bwlch height, with these values giving this hill 9.2m of drop, which is insufficient for it to be classified as a Welsh Highland Sub.
The full details for the hill are:
Group: Carnedd Llywelyn
Name: Craig yr Ysfa
OS 1:50,000 map: 115
Summit Height: 864.3m (LIDAR)
Summit Grid Reference: SH 69232 63638 (LIDAR)
Bwlch Height: 855.0m (LIDAR)
Bwlch Grid Reference: SH 69193 63707 (LIDAR)
Drop: 9.2m (LIDAR)
For the additions, deletions and reclassifications to the Welsh Highlands – Uchafion Cymru reported on Mapping Mountains please consult the following Change Registers:
Aled Williams and Myrddyn Phillips (June 2023)
Mapping Mountains - Hill Reclassifications - Welsh Highlands - Uchafion Cymru
Carnedd Fach (SH 658 626) – Welsh Highland Sub deletion (69th reclassification)
There has been a deletion to the listing of the Welsh Highlands – Uchafion Cymru, with the summit height, bwlch height and their locations, the drop and status of the hill derived from LIDAR analysis conducted by Aled Williams.
 |
| LIDAR image of Carnedd Fach (SH 658 626) |
The criteria for the list that this deletion applies to are:
Welsh Highlands – Uchafion Cymru – Welsh hills at or above 500m in height with 15m minimum drop, with an accompanying sub list entitled the Welsh Highland Subs, the criteria for which is all Welsh hills at or above 500m in height with 10m or more and below 15m of drop. This list is authored by Myrddyn Phillips and Aled Williams with the Introduction to the list published on Mapping Mountains in November 2015 and the latest update relating to the list published on Mapping Mountains in January 2023.
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| Welsh Highlands - Uchafion Cymru by Myrddyn Phillips and Aled Williams |
The name the hill is listed by is Carnedd Fach and it is adjoined to the Carnedd Llywelyn 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 road to its west and south, and has the town of Bethesda towards the north-west.
When the original list that later became known as the Welsh Highlands – Uchafion Cymru was first compiled, this hill was not included in the accompanying sub list, based on a basic levelling survey conducted by Myrddyn Phillips on the 25.07.98, which resulted in a 9.6m drop value.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
When the initial P10 sub list was completed in June 2020 this hill was listed as a Welsh Highland Sub with an estimated c 12m of drop, due to a misalignment of the basic levelling survey result with OS Maps data, and listed with a 966m summit height and an estimated c 954m bwlch height.
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 Highland Sub status is due to LIDAR analysis, resulting in a 965.1m summit height and a 956.2m bwlch height, with these values giving this hill 8.9m of drop, which is insufficient for it to be classified as a Welsh Highland Sub.
The full details for the hill are:
Group: Carnedd Llywelyn
Name: Carnedd Fach
OS 1:50,000 map: 115
Summit Height: 965.1m (LIDAR)
Summit Grid Reference: SH 65808 62620 (LIDAR)
Bwlch Height: 956.2m (LIDAR)
Bwlch Grid Reference: SH 65840 62664 (LIDAR)
Drop: 8.9m (LIDAR)
For the additions, deletions and reclassifications to the Welsh Highlands – Uchafion Cymru reported on Mapping Mountains please consult the following Change Registers:
Aled Williams and Myrddyn Phillips (June 2023)
Mapping Mountains - Hill Reclassifications - Welsh Highlands - Uchafion Cymru
Craig Yspio (SN 780 831) – Welsh Highland P15 addition (68th reclassification)
There has been an addition to the listing of the Welsh Highlands – Uchafion Cymru, with the summit height, bwlch height and their locations, the drop and status of the hill derived from LIDAR analysis conducted by Aled Williams and confirmed by a subsequent Trimble GeoXH 6000 survey conducted by Myrddyn Phillips.
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| Craig Yspio (SN 780 831). (Photo: Aled Williams) |
The criteria for the list that this addition applies to are:
Welsh Highlands – Uchafion Cymru – Welsh hills at or above 500m in height with 15m minimum drop, with an accompanying sub list entitled the Welsh Highland Subs, the criteria for which is all Welsh hills at or above 500m in height with 10m or more and below 15m of drop. This list is authored by Myrddyn Phillips and Aled Williams with the Introduction to the list published on Mapping Mountains in November 2015 and the latest update relating to the list published on Mapping Mountains in January 2023.
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| Welsh Highlands - Uchafion Cymru by Myrddyn Phillips and Aled Williams |
The name the hill is listed by is Craig Yspio and it is adjoined to the Pumlumon group of hills, which are situated in the north-western part of South Wales (Region B, Sub-Region B1), and it is positioned with the A44 road to its south-east, and has the village of Ponterwyd towards the south-west.
When the original list that later became known as the Welsh Highlands – Uchafion Cymru was first compiled, this hill was not included as either a Welsh Highland P15 or Welsh Highland Sub and therefore remained unclassified, as with only a relatively small uppermost 510m single ring contour and no summit or bwlch spot height, there was little map evidence available to suggest a hill existed that had a sufficient qualifying drop value.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
Latterly, when the initial P10 sub list was completed in June 2020, this hill was listed with an estimated c 6m of drop, based on a 513m summit height and an estimated c 507m bwlch height, the latter based on interpolation of 10m contouring between 500m – 510m.
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| The interactive DataMapWales gives a better portrayal of the P15 potential of this hill |
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.
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| LIDAR image of Craig Yspio (SN 780 831) |
The summit and bwlch of this hill have subsequently been surveyed with the Trimble GeoXH 6000, and it is this result that is being prioritised for this hill.
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| The Trimble GeoXH 6000 gathering data at the summit of Craig Yspio |
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| The Trimble GeoXH 6000 gathering data at the bwlch of Craig Yspio |
Therefore, the addition of this hill to Welsh Highland P15 status is due to LIDAR analysis and subsequently confirmed by a Trimble GeoXH 6000 survey, resulting in a 517.7m summit height and a 502.4m bwlch height, with these values giving this hill 15.3m of drop, which is sufficient for it to be classified as a Welsh Highland P15.
The full details for the hill are:
Group: Pumlumon
Name: Craig Yspio
OS 1:50,000 map: 135
Summit Height: 517.7m (converted to OSGM15)
Summit Grid Reference: SN 78042 83130
Bwlch Height: 502.4m (converted to OSGM15)
Bwlch Grid Reference: SN 78099 83176
Drop: 15.3m
For the additions, deletions and reclassifications to the Welsh Highlands – Uchafion Cymru reported on Mapping Mountains please consult the following Change Registers:
Aled Williams and Myrddyn Phillips (June 2023)
Mapping Mountains - Hill Reclassifications - Welsh Highlands - Uchafion Cymru
Pt. 585.6m (SJ 130 326) – Welsh Highland P15 reclassified to Welsh Highland Sub (67th reclassification)
There has been a reclassification to the listing of the Welsh Highlands – Uchafion Cymru, with the summit height, bwlch height and their locations, the drop and status of the hill derived from LIDAR analysis conducted by Aled Williams.
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| LIDAR image of Pt. 585.6m (SJ 130 326) |
The criteria for the list that this reclassification applies to are:
Welsh Highlands – Uchafion Cymru – Welsh hills at or above 500m in height with 15m minimum drop, with an accompanying sub list entitled the Welsh Highland Subs, the criteria for which is all Welsh hills at or above 500m in height with 10m or more and below 15m of drop. This list is authored by Myrddyn Phillips and Aled Williams with the Introduction to the list published on Mapping Mountains in November 2015 and the latest update relating to the list published on Mapping Mountains in January 2023.
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| Welsh Highlands - Uchafion Cymru by Myrddyn Phillips and Aled Williams |
The hill is being listed by the point (Pt. 585.6m) notation, and it is adjoined to the Craig Berwyn group of hills, which are situated in the eastern part of North Wales (Region A, Sub-Region A3), and it is positioned with a minor road to its north-east and south, and the B4500 road to its east north-east, and has the village of Llanarmon Dyffryn Ceiriog towards the east.
When the original list that later became known as the Welsh Highlands – Uchafion Cymru was first compiled, this hill was included as a Welsh Highland P15 and listed with 15m of drop, based on the 587m summit spot height and 572m bwlch spot height that appear on the Ordnance Survey 1:25,000 Explorer map.
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| 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 to Welsh Highland Sub status is due to LIDAR analysis, resulting in a 585.6m summit height and a 571.5m bwlch height, with these values giving this hill 14.15m of drop, which is insufficient for it to be classified as a Welsh Highland P15.
The full details for the hill are:
Group: Craig Berwyn
Name: Pt. 585.6m
OS 1:50,000 map: 125
Summit Height: 585.6m (LIDAR)
Summit Grid Reference: SJ 13031 32635 (LIDAR)
Bwlch Height: 571.5m (LIDAR)
Bwlch Grid Reference: SJ 12920 32539 (LIDAR)
Drop: 14.15m (LIDAR)
For the additions, deletions and reclassifications to the Welsh Highlands – Uchafion Cymru reported on Mapping Mountains please consult the following Change Registers:
Aled Williams and Myrddyn Phillips (June 2023)
Mapping Mountains - Hill Reclassifications - Welsh Highlands - Uchafion Cymru
Pt. 576.0m (SH 559 475) – Welsh Highland Sub reclassified to Welsh Highland P15 (66th reclassification)
There has been a reclassification to the listing of the Welsh Highlands – Uchafion Cymru, with the summit height, bwlch height and their locations, the drop and status of the hill derived from LIDAR analysis conducted by Aled Williams.
 |
| LIDAR image of Pt. 576.0m (SH 559 475) |
The criteria for the list that this reclassification applies to are:
Welsh Highlands – Uchafion Cymru – Welsh hills at or above 500m in height with 15m minimum drop, with an accompanying sub list entitled the Welsh Highland Subs, the criteria for which is all Welsh hills at or above 500m in height with 10m or more and below 15m of drop. This list is authored by Myrddyn Phillips and Aled Williams with the Introduction to the list published on Mapping Mountains in November 2015 and the latest update relating to the list published on Mapping Mountains in January 2023.
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| Welsh Highlands - Uchafion Cymru by Myrddyn Phillips and Aled Williams |
The hill is being listed by the point (Pt. 576.0m) notation, 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 B4418 road to its north, the A487 road to its west and the A4085 road to its north-east, and has the village of Beddgelert towards the east.
When the original list that later became known as the Welsh Highlands – Uchafion Cymru was first compiled, this hill was not included as a Welsh Highland Sub as with no separate uppermost ring contour on the contemporary Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map there was no map evidence to suggest that any form of hill with qualifying prominence existed.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
Since the original compilation of this list there are now a number of interactive maps originated from Ordnance Survey data that are available online. One of these is the mapping on the Magic Maps website, and this map gives this hill a summit spot height of 576m which is positioned at SH 55928 47522.
Another resource 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 Ordnance Survey maps and for this hill it also shows the 576m summit spot height.
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| Extract from the interactive mapping hosted on the WalkLakes website |
The details for this hill were also re-examined against the Ordnance Survey non-contour Vector Map Local hosted on the Geograph website and which is entitled the Interactive Coverage Map. This is another map that has many spot heights that do not appear on other publicly available Ordnance Survey maps and it also gives a 576m summit spot height.
The details for this hill were also re-assessed when the OS Maps website became available online. This is the replacement for OS Get-a-map and had contours at 5m intervals which were proving consistently more accurate compared to the 5m contours that sometimes appear on Ordnance Survey 1:25,000 Explorer maps and used to appear on the online Vector Map Local. This mapping has bwlch contouring between 560m – 565m, with interpolation giving an estimated c 562m bwlch height.
The above interactive mapping prompted the addition of this hill to Welsh Highland Sub status and it was listed with an estimated c 14m drop, based on the 576m summit spot height and an estimated c 562m bwlch height.
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 from Welsh Highland Sub status is due to LIDAR analysis, resulting in a 576.0m summit height and a 560.4m bwlch height, with these values giving this hill 15.6m of drop, which is sufficient for it to be classified as a Welsh Highland P15.
The full details for the hill are:
Group: Moel Hebog
Name: Pt. 576.0m
OS 1:50,000 map: 115
Summit Height: 576.0m (LIDAR)
Summit Grid Reference: SH 55928 47521 (LIDAR)
Bwlch Height: 560.4m (LIDAR)
Bwlch Grid Reference: SH 55885 47595 (LIDAR)
Drop: 15.6m (LIDAR)
For the additions, deletions and reclassifications to the Welsh Highlands – Uchafion Cymru reported on Mapping Mountains please consult the following Change Registers:
Aled Williams and Myrddyn Phillips (June 2023)
Mapping Mountains - Hill Reclassifications - Welsh Highlands - Uchafion Cymru
DUE TO A TRIMBLE GEOXH 6000 SURVEY THIS HILL HAS SUBSEQUENTLY BEEN REINSTATED TO WELSH HIGHLAND SUB STATUS
Elidir Fach (SH 603 613) – Welsh Highland Sub deletion (65th reclassification)
There has been a deletion to the listing of the Welsh Highlands – Uchafion Cymru, with the summit height, bwlch height and their locations, the drop and status of the hill derived from LIDAR analysis conducted by Aled Williams.
 |
| LIDAR image of Elidir Fach (SH 603 613) |
The criteria for the list that this deletion applies to are:
Welsh Highlands – Uchafion Cymru – Welsh hills at or above 500m in height with 15m minimum drop, with an accompanying sub list entitled the Welsh Highland Subs, the criteria for which is all Welsh hills at or above 500m in height with 10m or more and below 15m of drop. This list is authored by Myrddyn Phillips and Aled Williams with the Introduction to the list published on Mapping Mountains in November 2015 and the latest update relating to the list published on Mapping Mountains in January 2023.
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| Welsh Highlands - Uchafion Cymru by Myrddyn Phillips and Aled Williams |
The name the hill is listed by is Elidir Fach and it is adjoined to the Glyder Fawr 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 and west, the A5 road to its north-east and the A4086 road to its south-west, and has the village of Llanberis towards the south-west.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
When the initial P10 sub list was completed in June 2020 this hill was listed as a Welsh Highland Sub with 13.5m of drop, based on a basic levelling survey conducted by Myrddyn Phillips on the 22.05.98, and listed with an estimated c 800m summit height relative to its bwlch height, and a 786m bwlch height, with the latter based on detail on the enlarged-scale Ordnance Survey map hosted on the coflein.gov.uk 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 deletion of this hill from Welsh Highland Sub status is due to LIDAR analysis, resulting in a 794.5m summit height and a 784.7m bwlch height, with these values giving this hill 9.8m of drop, which is insufficient for it to be classified as a Welsh Highland Sub.
The full details for the hill are:
Group: Glyder Fawr
Name: Elidir Fach
OS 1:50,000 map: 115
Summit Height: 794.5m (LIDAR)
Summit Grid Reference: SH 60378 61339 (LIDAR)
Bwlch Height: 784.7m (LIDAR)
Bwlch Grid Reference: SH 60556 61279 (LIDAR)
Drop: 9.8m (LIDAR)
For the additions, deletions and reclassifications to the Welsh Highlands – Uchafion Cymru reported on Mapping Mountains please consult the following Change Registers:
Aled Williams and Myrddyn Phillips (June 2023)
Mapping Mountains - Hill Reclassifications - Welsh Highlands - Uchafion Cymru
Pt. 563.0m (SH 638 551) – Welsh Highland Sub addition (64th reclassification)
There has been an addition to the listing of the Welsh Highlands – Uchafion Cymru, with the summit height, bwlch height and their locations, the drop and status of the hill derived from LIDAR analysis conducted by Aled Williams and its status subsequently confirmed by a Trimble GeoXH 6000 survey also conducted by Aled Williams.
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| Pt. 563.0m (SH 638 551). Photo: Aled Williams |
The criteria for the list that this addition applies to are:
Welsh Highlands – Uchafion Cymru – Welsh hills at or above 500m in height with 15m minimum drop, with an accompanying sub list entitled the Welsh Highland Subs, the criteria for which is all Welsh hills at or above 500m in height with 10m or more and below 15m of drop. This list is authored by Myrddyn Phillips and Aled Williams with the Introduction to the list published on Mapping Mountains in November 2015 and the latest update relating to the list published on Mapping Mountains in January 2023.
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| Welsh Highlands - Uchafion Cymru by Myrddyn Phillips and Aled Williams |
The hill is being listed by the point (Pt. 563.0m) notation and it is adjoined to the Yr Wyddfa 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 A4086 road to its north and the A498 road to its east, and has the village of Llanberis towards the north-west.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
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. As this hill has now been surveyed with the Trimble GeoXH 6000, it is this result that is being prioritised.
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| Gathering data at the summit of Pt. 563.0m (SH 638 551). Photo: Aled Williams |
%20-%20bwlch%20survey.JPG) |
| Gathering data at the bwlch of Pt. 563.0m (summit at SH 638 551). Photo: Aled Williams |
Therefore, the addition of this hill to Welsh Highland Sub status is due to LIDAR analysis, with its status confirmed from a subsequent Trimble GeoXH 6000 survey, resulting in a 563.0m summit height and a 552.8m bwlch height, with these values giving this hill 10.2m of drop, which is sufficient for it to be classified as a Welsh Highland Sub.
The full details for the hill are:
Group: Yr Wyddfa
Name: Pt. 563.0m
OS 1:50,000 map: 115
Summit Height: 563.0m (converted to OSGM15)
Summit Grid Reference: SH 63821 55162
Bwlch Height: 552.8m (converted to OSGM15)
Bwlch Grid Reference: SH 63750 55175
Drop: 10.2m (LIDAR)
For the additions, deletions and reclassifications to the Welsh Highlands – Uchafion Cymru reported on Mapping Mountains please consult the following Change Registers:
Aled Williams and Myrddyn Phillips (June 2023)
Mapping Mountains - Hill Reclassifications - Welsh Highlands - Uchafion Cymru
Llechwedd Du (SH 893 446) – Welsh Highland P15 reclassified to Welsh Highland Sub (63rd reclassification)
Significant Height Revisions post for Llechwedd Du
There has been a reclassification to the listing of the Welsh Highlands – Uchafion Cymru, with the summit height, bwlch height and their locations, the drop and status of the hill derived from LIDAR analysis conducted for the Welsh Highlands – Uchafion Cymru list authored by Aled Williams and Myrddyn Phillips.
%20-%20LIDAR%20hill%201.jpg) |
| LIDAR image of Llechwedd Du (SH 893 446) |
The criteria for the list that this reclassification applies to are:
Welsh Highlands – Uchafion Cymru – Welsh hills at or above 500m in height with 15m minimum drop, with an accompanying sub list entitled the Welsh Highland Subs, the criteria for which is all Welsh hills at or above 500m in height with 10m or more and below 15m of drop. This list is authored by Myrddyn Phillips and Aled Williams with the Introduction to the list published on Mapping Mountains in November 2015 and the latest update relating to the list published on Mapping Mountains in January 2023.
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| Welsh Highlands - Uchafion Cymru by Myrddyn Phillips and Aled Williams |
The name the hill is listed by is Llechwedd Du and it is adjoined to the Carnedd y Filiast group of hills, which are situated in the central part of North Wales (Region A, Sub-Region A2), and is positioned with the A4212 road to its south and the B4501 road to its east, and has the town of Y Bala towards the south south-east and the village of Cerrigydrudion towards the north-east.
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| Extract from the Ordnance Survey 1:50,000 Landranger map |
When the original list that later became known as the Welsh Highlands – Uchafion Cymru was first compiled, this hill was included as a Welsh Highland Sub with 14m of drop, based on the 509m summit spot height that appears on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map and the 495m bwlch spot height that appears on the Ordnance Survey 1:25,000 Explorer map.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
The details for this hill were re-assessed when the OS Maps website became available online. This is the replacement for OS Get-a-map and had contours at 5m intervals which were consistently more accurate compared to the 5m contours that sometimes appeared on Ordnance Survey 1:25,000 Explorer maps and the online Vector Map Local. This re-assessment resulted in its reclassification to Welsh Highland P15 status and listed with an estimated c 16m of drop, based on an estimated c 511m summit height from interpolation of the 510m uppermost contour and the 495m bwlch spot height that appears on the Ordnance Survey 1:25,000 Explorer map.
 |
| Extract from the interactive mapping hosted on the OS Maps 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 back to Welsh Highland Sub status is due to LIDAR analysis, resulting in a 511.4m summit height and a 497.1m bwlch height, with these values giving this hill 14.3m of drop, which is insufficient for it to be classified as a Welsh Highland P15.
The full details for the hill are:
Group: Carnedd y Filiast
Name: Llechwedd Du
OS 1:50,000 map: 124, 125
Summit Height: 511.4m (LIDAR)
Summit Grid Reference: SH 89360 44629 (LIDAR)
Bwlch Height: 497.1m (LIDAR)
Bwlch Grid Reference: SH 89096 44273 (LIDAR)
Drop: 14.3m (LIDAR)
For the additions, deletions and reclassifications to the Welsh Highlands – Uchafion Cymru reported on Mapping Mountains please consult the following Change Registers:
Aled Williams and Myrddyn Phillips (May 2023)
Mapping Mountains - Hill Reclassifications - Welsh Highlands - Uchafion Cymru
Foel Fach (SH 944 423) – Welsh Highland Sub addition (62nd reclassification)
There has been an addition to the listing of the Welsh Highlands – Uchafion Cymru, with the summit height, bwlch height and their locations, the drop and status of the hill derived from LIDAR analysis conducted for the Welsh Highlands – Uchafion Cymru list authored by Aled Williams and Myrddyn Phillips.
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| LIDAR image of Foel Fach (SH 944 423) |
The criteria for the list that this addition applies to are:
Welsh Highlands – Uchafion Cymru – Welsh hills at or above 500m in height with 15m minimum drop, with an accompanying sub list entitled the Welsh Highland Subs, the criteria for which is all Welsh hills at or above 500m in height with 10m or more and below 15m of drop. This list is authored by Myrddyn Phillips and Aled Williams with the Introduction to the list published on Mapping Mountains in November 2015 and the latest update relating to the list published on Mapping Mountains in January 2023.
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| Welsh Highlands - Uchafion Cymru by Myrddyn Phillips and Aled Williams |
The name the hill is listed by is Foel Fach and it is adjoined to the Carnedd y Filiast group of hills, which are situated in the central part of North Wales (Region A, Sub-Region A2), and it is positioned with the B4501 road to its north-west, the A4212 road to its south-west, the A494 road to its south-east and the A5 road to its north-east, and has the town of Y Bala towards the south.
This hill was not included in the initial P10 sub list when it was completed in June 2020 as with a 544m summit height and an estimated c 536m bwlch height, based on enlarged scale Ordnance Survey mapping available online, these values gave this hill an estimated c 8m of drop.
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| 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 Highland Sub status is due to LIDAR analysis, resulting in a 544.5m summit height and a 534.4m bwlch height, with these values giving this hill 10.1m of drop, which is sufficient for it to be classified as a Welsh Highland Sub.
The full details for the hill are:
Group: Carnedd y Filiast
Name: Foel Fach
OS 1:50,000 map: 125
Summit Height: 544.5m (LIDAR)
Summit Grid Reference: SH 94433 42381 (LIDAR)
Bwlch Height: 534.4m (LIDAR)
Bwlch Grid Reference: SH 94485 42417 (LIDAR)
Drop: 10.1m (LIDAR)
For the additions, deletions and reclassifications to the Welsh Highlands – Uchafion Cymru reported on Mapping Mountains please consult the following Change Registers:
Aled Williams and Myrddyn Phillips (May 2023)
Mapping Mountains - Hill Reclassifications - Welsh Highlands - Uchafion Cymru
Pt. 592.5m (SH 648 474) – Welsh Highland Sub addition (61st reclassification)
There has been an addition to the listing of the Welsh Highlands – Uchafion Cymru, with the summit height, bwlch height and their locations, the drop and status of the hill derived from LIDAR analysis conducted for the Welsh Highlands – Uchafion Cymru list authored by Aled Williams and Myrddyn Phillips.
 |
| LIDAR image of Pt. 592.5m (SH 648 474) |
The criteria for the list that this addition applies to are:
Welsh Highlands – Uchafion Cymru – Welsh hills at or above 500m in height with 15m minimum drop, with an accompanying sub list entitled the Welsh Highland Subs, the criteria for which is all Welsh hills at or above 500m in height with 10m or more and below 15m of drop. This list is authored by Myrddyn Phillips and Aled Williams with the Introduction to the list published on Mapping Mountains in November 2015 and the latest update relating to the list published on Mapping Mountains in January 2023.
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| The Welsh Highlands - Uchafion Cymru by Myrddyn Phillips and Aled Williams |
The hill is being listed by the point (Pt. 592.5m) notation and it is adjoined to the Moelwyn Mawr group of hills, which are situated in the north-western part of North Wales (Region A, Sub-Region A2), and it is positioned with a minor road to its west, the A4085 road to its south-west, the A470 road to its east, and the A498 road farther to its north-west, and has the town of Blaenau Ffestiniog towards the east south-east.
This hill was not included in the initial P10 sub list when it was completed in June 2020 as with a 591m summit height and an estimated c 582m bwlch height, based on enlarged scale Ordnance Survey mapping available online, these values gave this hill an estimated c 9m of drop.
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| 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 Highland Sub status is due to LIDAR analysis, resulting in a 592.5m summit height and a 582.2m bwlch height, with these values giving this hill 10.3m of drop, which is sufficient for it to be classified as a Welsh Highland Sub.
The full details for the hill are:
Group: Moelwyn Mawr
Name: Pt. 592.5m
OS 1:50,000 map: 115
Summit Height: 592.5m (LIDAR)
Summit Grid Reference: SH 64805 47425 (LIDAR)
Bwlch Height: 582.2m (LIDAR)
Bwlch Grid Reference: SH 64974 47586 (LIDAR)
Drop: 10.3m (LIDAR)
For the additions, deletions and reclassifications to the Welsh Highlands – Uchafion Cymru reported on Mapping Mountains please consult the following Change Registers:
Aled Williams and Myrddyn Phillips (May 2023)
Mapping Mountains - Hill Reclassifications - Welsh Highlands - Uchafion Cymru
Pt. 571.3m (SH 661 498) – Welsh Highland Sub addition (60th reclassification)
There has been an addition to the listing of the Welsh Highlands – Uchafion Cymru, with the summit height, bwlch height and their locations, the drop and status of the hill derived from LIDAR analysis conducted for the Welsh Highlands – Uchafion Cymru list authored by Aled Williams and Myrddyn Phillips.
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| LIDAR image of Pt. 571.3m (SH 661 498) |
The criteria for the list that this addition applies to are:
Welsh Highlands – Uchafion Cymru – Welsh hills at or above 500m in height with 15m minimum drop, with an accompanying sub list entitled the Welsh Highland Subs, the criteria for which is all Welsh hills at or above 500m in height with 10m or more and below 15m of drop. This list is authored by Myrddyn Phillips and Aled Williams with the Introduction to the list published on Mapping Mountains in November 2015 and the latest update relating to the list published on Mapping Mountains in January 2023.
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| Welsh Highlands - Uchafion Cymru by Myrddyn Phillips and Aled Williams |
The hill is being listed by the point (Pt. 571.3m) notation and it is adjoined to the Moelwyn Mawr group of hills, which are situated in the north-western part of North Wales (Region A, Sub-Region A2), and it is positioned with the A498 road to its north-west, a minor road to its west, and the A470 road to its east, and has the town of Blaenau Ffestiniog towards the south-east.
This hill was not included in the initial P10 sub list when it was completed in June 2020 as with an estimated c 572m summit height and an estimated c 564m bwlch height, with both heights on interpolation of 10m contouring, these values gave this hill an estimated c 8m of drop.
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| 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 Highland Sub status is due to LIDAR analysis, resulting in a 571.3m summit height and a 560.9m bwlch height, with these values giving this hill 10.4m of drop, which is sufficient for it to be classified as a Welsh Highland Sub.
The full details for the hill are:
Group: Moelwyn Mawr
Name: Pt. 571.3m
OS 1:50,000 map: 115
Summit Height: 571.3m (LIDAR)
Summit Grid Reference: SH 66153 49880 (LIDAR)
Bwlch Height: 560.9m (LIDAR)
Bwlch Grid Reference: SH 66223 49897 (LIDAR)
Drop: 10.4m (LIDAR)
For the additions, deletions and reclassifications to the Welsh Highlands – Uchafion Cymru reported on Mapping Mountains please consult the following Change Registers:
Aled Williams and Myrddyn Phillips (May 2023)
Mapping Mountains - Hill Reclassifications - Welsh Highlands - Uchafion Cymru
Pt. 531.3m (SH 658 469) – Welsh Highland Sub addition (59th reclassification)
There has been an addition to the listing of the Welsh Highlands – Uchafion Cymru, with the summit height, bwlch height and their locations, the drop and status of the hill derived from LIDAR analysis conducted for the Welsh Highlands – Uchafion Cymru list authored by Aled Williams and Myrddyn Phillips.
%20-%20LIDAR%20hill%201%20-%20Aled.jpg) |
| LIDAR image of Pt. 531.3m (SH 658 469) |
The criteria for the list that this addition applies to are:
Welsh Highlands – Uchafion Cymru – Welsh hills at or above 500m in height with 15m minimum drop, with an accompanying sub list entitled the Welsh Highland Subs, the criteria for which is all Welsh hills at or above 500m in height with 10m or more and below 15m of drop. This list is authored by Myrddyn Phillips and Aled Williams with the Introduction to the list published on Mapping Mountains in November 2015 and the latest update relating to the list published on Mapping Mountains in January 2023.
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| Welsh Highlands - Uchafion Cymru by Myrddyn Phillips and Aled Williams |
The hill is being listed by the point (Pt. 531.3m) notation and it is adjoined to the Moelwyn Mawr group of hills, which are situated in the north-western part of North Wales (Region A, Sub-Region A2), and it is positioned with a minor road to its west, the A4085 road to its south-west, the B4410 road to its south and the A470 road to its east, and has the town of Blaenau Ffestiniog towards the east south-east.
This hill was not included in the initial P10 sub list when it was completed in June 2020 as with a 531m 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 523m bwlch height, based on interpolation of 10m contouring between 520m – 530m, these values gave this hill an estimated c 8m of drop.
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| 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 Highland Sub status is due to LIDAR analysis, resulting in a 531.3m summit height and a 520.6m bwlch height, with these values giving this hill 10.6m of drop, which is sufficient for it to be classified as a Welsh Highland Sub.
The full details for the hill are:
Group: Moelwyn Mawr
Name: Pt. 531.3m
OS 1:50,000 map: 115
Summit Height: 531.3m (LIDAR)
Summit Grid Reference: SH 65884 46911 (LIDAR)
Bwlch Height: 520.6m (LIDAR)
Bwlch Grid Reference: SH 65971 46821 (LIDAR)
Drop: 10.6m (LIDAR)
For the additions, deletions and reclassifications to the Welsh Highlands – Uchafion Cymru reported on Mapping Mountains please consult the following Change Registers:
Aled Williams and Myrddyn Phillips (May 2023)
Mapping Mountains - Hill Reclassifications - Welsh Highlands - Uchafion Cymru
Cefn y Cerrig (SH 674 545) – Welsh Highland Sub addition (58th reclassification)
There has been an addition to the listing of the Welsh Highlands – Uchafion Cymru, 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 Aled Williams.
 |
| Cefn y Cerrig (SH 674 545) (Photo: Aled Williams) |
The criteria for the list that this addition applies to are:
Welsh Highlands – Uchafion Cymru – Welsh hills at or above 500m in height with 15m minimum drop, with an accompanying sub list entitled the Welsh Highland Subs, the criteria for which is all Welsh hills at or above 500m in height with 10m or more and below 15m of drop. This list is authored by Myrddyn Phillips and Aled Williams with the Introduction to the list published on Mapping Mountains in November 2015 and the latest update relating to the list published on Mapping Mountains in January 2023.
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| Welsh Highlands - Uchafion Cymru by Myrddyn Phillips and Aled Williams |
The name the hill is listed by is Cefn y Cerrig and it is adjoined to the Moel Siabod group of hills, which are situated in the north-western part of North Wales (Region A, Sub-Region A2), and it is positioned with the A4086 road to its north, the A498 road to its west and the A470 road to its south-east, and has the village of Capel Curig towards the north-east.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
Prior to the survey with the Trimble GeoXH 6000 this hill was initially listed with an estimated c 9m of drop, based on the 502m 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 493m bwlch height, based on interpolation of 10m contouring between 490m – 500m.
 |
| The Trimble GeoXH 6000 gathering data at the summit of Cefn y Cerrig. (Photo: Aled Williams) |
Therefore, the addition of this hill to Welsh Highland Sub status is due to a Trimble GeoXH 6000 survey, resulting in a 502.0m summit height and a 491.2m bwlch height, with these values giving this hill 10.8m of drop, which is sufficient for it to be classified as a Welsh Highland Sub.
The full details for the hill are:
Group: Moel Siabod
Name: Cefn y Cerrig
OS 1:50,000 map: 115
Summit Height: 502.0m (converted to OSGM15)
Summit Grid Reference: SH 67480 54509
Bwlch Height: 491.2m (converted to OSGM15)
Bwlch Grid Reference: SH 67511 54413
Drop: 10.8m
For the additions, deletions and reclassifications to the Welsh Highlands – Uchafion Cymru reported on Mapping Mountains please consult the following Change Registers:
Aled Williams and Myrddyn Phillips (May 2023)
Mapping Mountains - Hill Reclassifications - Welsh Highlands - Uchafion Cymru
Cefn Blaen Merin (SN 812 810) – Welsh Highland P15 reclassified to Welsh Highland Sub (57th reclassification)
There has been a reclassification to the listing of the Welsh Highlands – Uchafion Cymru, with the summit height, bwlch height and their locations, the drop and status of the hill derived from LIDAR analysis conducted for the Welsh Highlands – Uchafion Cymru list authored by Aled Williams and Myrddyn Phillips.
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| LIDAR image of Cefn Blaen Merin (SN 812 810) |
The criteria for the list that this reclassification applies to are:
Welsh Highlands – Uchafion Cymru – Welsh hills at or above 500m in height with 15m minimum drop, with an accompanying sub list entitled the Welsh Highland Subs, the criteria for which is all Welsh hills at or above 500m in height with 10m or more and below 15m of drop. This list is authored by Myrddyn Phillips and Aled Williams with the Introduction to the list published on Mapping Mountains in November 2015 and the latest update relating to the list published on Mapping Mountains in January 2023.
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| Welsh Highlands - Uchafion Cymru by Myrddyn Phillips and Aled Williams |
The name the hill is listed by is Cefn Blaen Merin and it is adjoined to the Y Garn group of hills, which are situated in the northern part of South Wales (Region B, Sub-Region B1), and it is positioned with the A44 road to its north, the B4343 road and A4120 road to its west and a minor road to its south, and has the village of Ponterwyd towards the west.
This hill was not included in the list that later became known as the Welsh Highlands – Uchafion Cymru when the qualifying P15s were first compiled, however it was listed as a potential qualifying hill as it has an uppermost 550m ring contour estimated as c 552m in height and bwlch contouring between 530m - 540m with interpolation placing the height of the bwlch as an estimated c 537m.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
This hill was subsequently surveyed using a basic levelling staff on the 20th November 2005 by Myrddyn Phillips, resulting in a 49½ft/15.1m drop value, which was sufficient for it to be classified in the main P15 list. However, the margin of uncertainty applicable to the basic levelling method of surveying over the distance between bwlch and summit and the terrain of this hill is approximately +/- 0.5m.
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 Highland Sub status is due to LIDAR analysis, resulting in a 552.9m summit height and a 538.1m bwlch height, with these values giving this hill 14.8m of drop, which is insufficient for it to be classified as a Welsh Highland P15.
The full details for the hill are:
Group: Y Garn
Name: Cefn Blaen Merin
OS 1:50,000 map: 135, 136
Summit Height: 552.9m (LIDAR)
Summit Grid Reference: SN 81271 81064 (LIDAR)
Bwlch Height: 538.1m (LIDAR)
Bwlch Grid Reference: SN 81424 81034 & SN 81425 81035 & SN 81427 81039 (LIDAR)
Drop: 14.8m (LIDAR)
For the additions, deletions and reclassifications to the Welsh Highlands – Uchafion Cymru reported on Mapping Mountains please consult the following Change Registers:
Aled Williams and Myrddyn Phillips (May 2023)
Mapping Mountains - Hill Reclassifications - Welsh Highlands - Uchafion Cymru
Bryn Llochesau (SN 824 807) – Welsh Highland Sub deletion (56th reclassification)
There has been a deletion to the listing of the Welsh Highlands – Uchafion Cymru, with the summit height, bwlch height and their locations, the drop and status of the hill derived from LIDAR analysis conducted for the Welsh Highlands – Uchafion Cymru list authored by Aled Williams and Myrddyn Phillips.
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| LIDAR image of Bryn Llochesau (SN 824 807) |
The criteria for the list that this deletion applies to are:
Welsh Highlands – Uchafion Cymru – Welsh hills at or above 500m in height with 15m minimum drop, with an accompanying sub list entitled the Welsh Highland Subs, the criteria for which is all Welsh hills at or above 500m in height with 10m or more and below 15m of drop. This list is authored by Myrddyn Phillips and Aled Williams with the Introduction to the list published on Mapping Mountains in November 2015 and the latest update relating to the list published on Mapping Mountains in January 2023.
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| Welsh Highlands - Uchafion Cymru by Myrddyn Phillips and Aled Williams |
The name the hill is listed by is Bryn Llochesau and it is adjoined to the Y Garn group of hills, which are situated in the northern part of South Wales (Region B, Sub-Region B1), and it is positioned with the A44 road to its north, the B4343 road and A4120 road to its west and a minor road to its south, and has the village of Ponterwyd towards the west.
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| Extract from the Ordnance Survey 1:50,000 Landranger map |
When the initial P10 sub list was completed in June 2020 this hill was listed with an estimated c 10m of drop, based on the 1849ft (563.6m) imperial summit height that appeared on the Ordnance Survey series of Six-Inch maps (rounded up to 564m on the Ordnance Survey 1:50,000 Landranger map) and an estimated c 554m bwlch height based on interpolation of 10m contouring between 550m – 560m.
%20-%20Six%20Inch.jpg) |
| Extract from the Ordnance Survey series of Six-Inch maps |
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 Highland Sub status is due to LIDAR analysis, resulting in a 563.8m summit height and a 554.1m bwlch height, with these values giving this hill 9.7m of drop, which is insufficient for it to be classified as a Welsh Highland Sub.
The full details for the hill are:
Group: Y Garn
Name: Bryn Llochesau
OS 1:50,000 map: 135, 136
Summit Height: 563.8m (LIDAR)
Summit Grid Reference: SN 82447 80795 (LIDAR)
Bwlch Height: 554.1m (LIDAR)
Bwlch Grid Reference: SN 82319 80472 (LIDAR)
Drop: 9.7m (LIDAR)
For the additions, deletions and reclassifications to the Welsh Highlands – Uchafion Cymru reported on Mapping Mountains please consult the following Change Registers:
Aled Williams and Myrddyn Phillips (April 2023)
Mapping Mountains - Hill Reclassifications - Welsh Highlands - Uchafion Cymru
Craig Eigiau (SH 712 646) – Welsh Highland Sub addition (55th reclassification)
Significant Height Revisions post for Craig Eigiau
There has been an addition to the listing of the Welsh Highlands – Uchafion Cymru, 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 Aled Williams.
 |
| Craig Eigiau (SH 712 646) (Photo: Aled Williams) |
The criteria for the list that this addition applies to are:
Welsh Highlands – Uchafion Cymru – Welsh hills at or above 500m in height with 15m minimum drop, with an accompanying sub list entitled the Welsh Highland Subs, the criteria for which is all Welsh hills at or above 500m in height with 10m or more and below 15m of drop. This list is authored by Myrddyn Phillips and Aled Williams with the Introduction to the list published on Mapping Mountains in November 2015 and the latest update relating to the list published on Mapping Mountains in January 2023.
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| Welsh Highlands - Uchafion Cymru by Myrddyn Phillips and Aled Williams |
The name the hill is listed by is Craig Eigiau and it is adjoined to the Carnedd Llywelyn 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 north-east, the A5 road to its south-west and the B5106 road and the A470 road to its east, and has the town of Llanrwst towards the east south-east.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
Prior to the survey with the Trimble GeoXH 6000 this hill was listed with 9.7m of drop, based on a 688.1m summit height and a 678.4m bwlch height, with both heights derived from LIDAR analysis conducted by Aled Williams. Due to the marginal nature in the drop ascertained from LIDAR analysis, this hill was prioritised for a Trimble GeoXH 6000 survey and it is this result that is being prioritised.
 |
| The Trimble GeoXH 6000 gathering data at the summit of Craig Eigiau (SH 712 646) (Photo: Aled Williams) |
Therefore, the addition of this hill to Welsh Highland Sub status is due to a Trimble GeoXH 6000 survey, resulting in a 688.4m summit height and a 678.2m bwlch height, with these values giving this hill 10.2m of drop, which is sufficient for it to be classified as a Welsh Highland Sub.
The full details for the hill are:
Group: Carnedd Llywelyn
Name: Craig Eigiau
OS 1:50,000 map: 115
Summit Height: 688.4m (converted to OSGM15)
Summit Grid Reference: SH 71280 64670
Bwlch Height: 678.2m (converted to OSGM15)
Bwlch Grid Reference: SH 71218 64674
Drop: 10.2m
For the additions, deletions and reclassifications to the Welsh Highlands – Uchafion Cymru reported on Mapping Mountains please consult the following Change Registers:
Aled Williams and Myrddyn Phillips (April 2023)
Mapping Mountains - Hill Reclassifications - Welsh Highlands - Uchafion Cymru
Pt. 524.3m (SH 661 457) – Welsh Highland Sub addition (54th reclassification)
There has been an addition to the listing of the Welsh Highlands – Uchafion Cymru, 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 Aled Williams.
 |
| Pt. 524.3m (SH 661 457) (Photo: Aled Williams) |
The criteria for the list that this addition applies to are:
Welsh Highlands – Uchafion Cymru – Welsh hills at or above 500m in height with 15m minimum drop, with an accompanying sub list entitled the Welsh Highland Subs, the criteria for which is all Welsh hills at or above 500m in height with 10m or more and below 15m of drop. This list is authored by Myrddyn Phillips and Aled Williams with the Introduction to the list published on Mapping Mountains in November 2015 and the latest update relating to the list published on Mapping Mountains in January 2023.
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| Welsh Highlands - Uchafion Cymru by Myrddyn Phillips and Aled Williams |
The hill is being listed by the point (Pt. 524.3m) notation and it is adjoined to the Moelwyn Mawr group of hills, which are situated in the north-western part of North Wales (Region A, Sub-Region A2), and it is positioned with the A4085 road to its west, the A487 road to its south and the A496 road to its south-east, and has the town of Blaenau Ffestiniog towards the east.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
When the initial P10 sub list was completed in June 2020 this hill was not included, as the contemporary Ordnance Survey 1:25,000 Explorer map only has two small uppermost 520m contours without any summit or bwlch spot height.
However, the hill was surveyed by Aled Williams using the Trimble GeoXH 6000. Upon investigation it was judged that the natural drop of this hill exceeds 10m, with the area of the bwlch complicated by a dam and leat. The conclusion being that the natural bwlch was either under the dam or further north past the leat, but for now we are taking the bottom of the dam as the critical point of the bwlch.
 |
| The Trimle GeoXH 6000 gathering data at the summit of Pt. 524.3m (SH 661 457) (Photo: Aled Williams) |
 |
| Looking down at the bwlch (Photo: Aled Williams) |
Therefore, the addition of this hill to Welsh Highland Sub status is due to a Trimble GeoXH 6000 survey, resulting in a 524.3m summit height and a 513.5m bwlch height, with these values giving this hill 10.7m of drop, which is sufficient for it to be classified as a Welsh Highland Sub.
The full details for the hill are:
Group: Moelwyn Mawr
Name: Pt. 524.3m
OS 1:50,000 map: 124
Summit Height: 524.3m (converted to OSGM15)
Summit Grid Reference: SH 66117 45783
Bwlch Height: 513.5m (converted to OSGM15)
Bwlch Grid Reference: SH 66131 45774
Drop: 10.7m
For the additions, deletions and reclassifications to the Welsh Highlands – Uchafion Cymru reported on Mapping Mountains please consult the following Change Registers:
Aled Williams and Myrddyn Phillips (April 2023)
Mapping Mountains - Hill Reclassifications - Welsh Highlands - Uchafion Cymru
Craig Ysgafn (SH 659 443) – Welsh Highland Sub addition (53rd reclassification)
There has been an addition to the listing of the Welsh Highlands – Uchafion Cymru, 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 Aled Williams.
 |
| Craig Ysgafn (Photo: Aled Williams) |
The criteria for the list that this addition applies to are:
Welsh Highlands – Uchafion Cymru – Welsh hills at or above 500m in height with 15m minimum drop, with an accompanying sub list entitled the Welsh Highland Subs, the criteria for which is all Welsh hills at or above 500m in height with 10m or more and below 15m of drop. This list is authored by Myrddyn Phillips and Aled Williams with the Introduction to the list published on Mapping Mountains in November 2015 and the latest update relating to the list published on Mapping Mountains in January 2023.
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| Welsh Highlands - Uchafion Cymru by Myrddyn Phillips and Aled Williams |
The name the hill is listed by is Craig Ysgafn and it is adjoined to the Moelwyn Mawr group of hills, which are situated in the north-western part of North Wales (Region A, Sub-Region A2), and it is positioned with the A4085 road to its west, the A487 road to its south and the A496 road to its east, and has the town of Blaenau Ffestiniog towards the north-east.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
Prior to the survey with the Trimble GeoXH 6000 this hill was listed with 9.9m of drop, based on a 687.7m summit height and a 677.8m bwlch height, with both heights derived from LIDAR analysis conducted by Aled Williams, with a previous basic levelling survey conducted by Myrddyn Phillips on the 18.04.98 giving 10.0m of drop.
Due to the marginal nature in the drop ascertained from LIDAR analysis, this hill was prioritised for a Trimble GeoXH 6000 survey and it is this result that is being prioritised.
Therefore, the addition of this hill to Welsh Highland Sub status is due to a Trimble GeoXH 6000 survey, resulting in a 688.3m summit height and a 678.0m bwlch height, with these values giving this hill 10.3m of drop, which is sufficient for it to be classified as a Welsh Highland Sub.
The full details for the hill are:
Group: Moelwyn Mawr
Name: Craig Ysgafn
OS 1:50,000 map: 124
Summit Height: 688.3m (converted to OSGM15)
Summit Grid Reference: SH 65973 44394
Bwlch Height: 678.0m (converted to OSGM15)
Bwlch Grid Reference: SH 65960 44382
Drop: 10.3m
For the additions, deletions and reclassifications to the Welsh Highlands – Uchafion Cymru reported on Mapping Mountains please consult the following Change Registers:
Aled Williams and Myrddyn Phillips (March 2023)
Mapping Mountains - Hill Reclassifications - Welsh Highlands - Uchafion Cymru
Tryfan (SH 663 593) – Welsh Highland Sub deletion (52nd reclassification)
There has been a deletion to the listing of the Welsh Highlands – Uchafion Cymru, 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 Aled Williams.
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| Tryfan (SH 663 593) (Photo: Aled Williams) |
The criteria for the list that this deletion applies to are:
Welsh Highlands – Uchafion Cymru – Welsh hills at or above 500m in height with 15m minimum drop, with an accompanying sub list entitled the Welsh Highland Subs, the criteria for which is all Welsh hills at or above 500m in height with 10m or more and below 15m of drop. This list is authored by Myrddyn Phillips and Aled Williams with the Introduction to the list published on Mapping Mountains in November 2015 and the latest update relating to the list published on Mapping Mountains in January 2023.
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| Welsh Highlands - Uchafion Cymru by Myrddyn Phillips and Aled Williams |
The name the hill is listed by is Tryfan and it is adjoined to the Glyder Fawr 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 road to its north and the A4086 road to its south, and has the village of Capel Curig towards the east south-east.
When the initial P10 sub list was completed in June 2020 this hill was not included. Revision of the list based on basic levelling surveys conducted by Myrddyn Phillips was completed the following month and this hill was then listed with 10.0m of drop, based on a basic levelling survey conducted on the 01.05.98, and listed with a 910m summit height that appears as a spot height on the Ordnance Survey 1:25,000 Explorer map and a 900m bwlch height, based on the basic levelling survey result compared to the summit spot height.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
Due to the marginal nature in both listed drop and the accuracy of the surveying method that this was obtained from, this hill was prioritised for a Trimble GeoXH 6000 survey and this has now taken place resulting in its deletion from sub status.
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| A precarious position for a survey - Trimble attached to a dog lead and held in situ (Photo: Aled Williams) |
Therefore, the deletion of this hill from Welsh Highland Sub status is due to a Trimble GeoXH 6000 survey, resulting in a 910.8m summit height and a 901.6m bwlch height, with these values giving this hill 9.2m of drop, which is insufficient for it to be classified as a Welsh Highland Sub.
The full details for the hill are:
Group: Glyder Fawr
Name: Tryfan
OS 1:50,000 map: 115
Summit Height: 910.8m (converted to OSGM15)
Summit Grid Reference: SH 66393 59332
Bwlch Height: 901.6m (converted to OSGM15)
Bwlch Grid Reference: SH 66378 59359
Drop: 9.2m
For the additions, deletions and reclassifications to the Welsh Highlands – Uchafion Cymru reported on Mapping Mountains please consult the following Change Registers:
Aled Williams and Myrddyn Phillips (March 2023)
On 7th January 2023
the Sub hills accompanying the main listing of the Welsh Highlands – Uchafion Cymru
were amended. The 490m Subs and 490m
Double Subs have been dispensed with, and the remaining 500m Subs are now
entitled the Welsh Highland Subs and their criteria amended to include all
Welsh hills at and above 500m in height with 10m or more and below 15m of drop.
Mapping Mountains - Hill Reclassifications - The Welsh Highlands - Uchafion Cymru
Chwarel Graig Ddu (SH 725 455) – Uchaf addition (51st reclassification)
Survey post for Chwarel Graig Ddu
There has been an addition to the listing of The Welsh Highlands – Uchafion Cymru, with the summit height, bwlch height and their locations, the drop and status of the hill derived from detail on contemporary maps.
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| Chwarel Graig Ddu (SH 725 455) |
The criteria for the list that this addition applies to are:
The Welsh Highlands – Uchafion Cymru – This is the revised draft title for the Welsh 500m P15s list that takes in all hills in Wales at or above 500m in height with 15m minimum drop. The list is co-authored by Myrddyn Phillips and Aled Williams with the Introduction to the list being published on Mapping Mountains in November 2015 and an update relating to the list appearing on Mapping Mountains on the 19th June 2019.
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| The Welsh Highlands - Uchafion Cymru by Myrddyn Phillips and Aled Williams |
The name the hill is listed by is Chwarel Graig Ddu, and it is adjoined to the Arenig Fach group of hills, which are situated in the north-western part of North Wales (Region A, Sub-Region A2), and it is positioned with the A470 road to its west and the B4391 road to its south, and has the town of Blaenau Ffestiniog towards the west.
This hill was not included in the original list of Welsh 500m P15s that later became known as Yr Uchafion and latterly as The Welsh Highlands – Uchafion Cymru, as because it is a part of a working quarry the contemporary Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map do not show any spot heights or contours, therefore the hill seemed not to exist.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
Since the original compilation of this list there have been a number of 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 were digitally updated such as the Ordnance Survey Vector Map Local that was hosted on the Geograph website and which was entitled the Interactive Coverage Map, whilst others are current and digitally updated such as the interactive mapping on the Magic Maps and WalkLakes websites.
One of the resources recently available online is the mapping on the OS Maps website. This is the replacement for OS Get-a-map and until recent times had contours at 5m intervals which were proving consistently more accurate compared to the 5m contours that sometimes appear on the Ordnance Survey 1:25,000 Explorer map and used to appear on the online Vector Map Local. Although the mapping on the OS Maps website no longer has contours at 5m intervals, such contours are represented on other mapping available online and for this hill this mapping has an uppermost 610m ring contour and bwlch contouring between 590m – 595m, with these contours giving this hill a drop value exceeding the minimum 15m to qualify for this list.
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| Extract from the online map showing 5m contouring |
The hill has subsequently been inspected from adjacent hillsides and its validity confirmed and as a quarry road passes over its summit area it is considered solid and stable.
Therefore, the addition of this hill to Uchaf status is due to detail on contemporary online mapping with a subsequent inspection from adjacent hillsides undertaken to confirm its validity, resulting in a 613m summit height and a 592m bwlch height, with these values giving this hill 21m of drop, which is sufficient for it to be classified as an Uchaf.
The full details for the hill are:
Group: Arenig Fach
Name: Chwarel Graig Ddu
OS 1:50,000 map: 115
Summit Height: 613m
Summit Grid Reference: SH 72505 45533
Bwlch Height: 592m
Bwlch Grid Reference: SH 72456 45744
Drop: 21m
For the additions, deletions and reclassifications to The Welsh Highlands – Uchafion Cymru reported on Mapping Mountains please consult the following Change Registers:
The Welsh 500m P15s (Yr Uchafion)
The Welsh 500m P15s (Yr Uchafion) – 500m Subs
The Welsh 500m P15s (Yr Uchafion) – 490m Subs
The Welsh 500m P15s (Yr Uchafion) – Double Subs
Myrddyn Phillips and Aled Williams (June 2022)
Mapping Mountains - Hill Reclassifications - The Welsh Highlands - Uchafion Cymru
Pt. 581.7m (SJ 086 373) – 500m Sub-Uchaf deletion (50th reclassification)
There has been a deletion to the listing of The Welsh Highlands – Uchafion Cymru, 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 and Aled Williams.
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| Pt. 581.7m (SJ 086 373) |
The criteria for the list that this deletion applies to are:
The Welsh Highlands – Uchafion Cymru – This is the revised draft title for the Welsh 500m P15s list that takes in all hills in Wales at or above 500m in height with 15m minimum drop. Accompanying the main list are three sub lists, these are; 500m Sub-Uchaf, 490m Sub-Uchaf and the Double Sub category, with this hill being deleted as a 500m Sub-Uchaf. The criteria for which are all Welsh hills at or above 500m in height with 14m or more and below 15m of drop. The list is co-authored by Myrddyn Phillips and Aled Williams with the Introduction to the list being published on Mapping Mountains in November 2015 and an update relating to the list appearing on Mapping Mountains on the 19th June 2019.
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| The Welsh Highlands - Uchafion Cymru by Myrddyn Phillips and Aled Williams |
As the authors do not know an appropriate name for the hill either from historic research or from local enquiry it is being listed by the point (Pt. 581.7m) notation, and it is adjoined to the Y Berwyn group of hills, which are situated in the south-eastern part of North Wales (Region A, Sub-Region A4), and it is positioned with the A5 road to its north, the B4401 road to its west and the B4391 road to its south-west, and has the village of Cynwyd towards the north-west.
This hill was not included as a P14 Sub in the original list of Welsh 500m P15s that later became known as Yr Uchafion and latterly as The Welsh Highlands – Uchafion Cymru, as with a 582m summit spot height and bwlch contouring between 570m – 580m that appear on the Ordnance Survey 1:25,000 Explorer map, this contouring implied that the hill did not have sufficient drop to be considered for P14 500m Sub-Uchaf status.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
Since the original compilation of this list there are now a number of interactive maps originated from Ordnance Survey data that are available online. One of these is the mapping on the OS Maps website. This is the replacement for OS Get-a-map and used to have contours at 5m intervals which proved consistently more accurate compared to the 5m contours that sometimes appear on the Ordnance Survey 1:25,000 Explorer map and used to appear on the online Vector Map Local. This mapping had an uppermost 580m ring contour and bwlch contouring between 565m – 570m, with interpolation giving an estimated bwlch height of c 568m, therefore with an estimated c 14m of drop it was added as a 500m Sub-Uchaf. Due to this addition the hill was prioritised for a Trimble GeoXH 6000 survey and this has now taken place resulting in its deletion from sub status.
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| The Trimble GeoXH 6000 gathering data at the summit of Pt. 581.7m |
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| The Trimble GeoXH 6000 gathering data at the bwlch of Pt. 581.7m |
Therefore, the deletion of this hill from 500m Sub-Uchaf status is due to a Trimble GeoXH 6000 survey, resulting in a 581.7m summit height and a 568.7m bwlch height, with these values giving this hill 13.0m of drop, which is insufficient for it to be classified as a 500m Sub-Uchaf.
The full details for the hill are:
Group: Y Berwyn
Name: Pt. 581.7m
OS 1:50,000 map: 125
Summit Height: 581.7m (converted to OSGM15)
Summit Grid Reference: SJ 08664 37360
Bwlch Height: 568.7m (converted to OSGM15)
Bwlch Grid Reference: SJ 08659 37320
Drop: 13.0m
For the additions, deletions and reclassifications to The Welsh Highlands – Uchafion Cymru reported on Mapping Mountains please consult the following Change Registers:
The Welsh 500m P15s (Yr Uchafion)
The Welsh 500m P15s (Yr Uchafion) – 500m Subs
The Welsh 500m P15s (Yr Uchafion) – 490m Subs
The Welsh 500m P15s (Yr Uchafion) – Double Subs
Myrddyn Phillips and Aled Williams (June 2020)
Mapping Mountains - Hill Reclassifications - The Welsh Highlands - Uchafion Cymru
Cwar Blaen Dyffryn (SO 098 148) – 490m Sub-Uchaf addition (49th reclassification)
There has been an addition to the listing of The Welsh Highlands – Uchafion Cymru, with the summit height, bwlch height and their locations, the drop and status of the hill derived from LIDAR analysis conducted by Aled Williams.
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| LIDAR image of Cwar Blaen Dyffryn (SO 098 148) |
The criteria for the list that this addition applies to are:
The Welsh Highlands – Uchafion Cymru – This is the revised draft title for the Welsh 500m P15s list that takes in all hills in Wales at or above 500m in height with 15m minimum drop. Accompanying the main list are three sub lists, these are; 500m Sub-Uchaf, 490m Sub-Uchaf and the Double Sub category, with this hill being added as a 490m Sub-Uchaf. The criteria for which are all Welsh hills at or above 490m and below 500m in height with 15m minimum drop. The list is co-authored by Myrddyn Phillips and Aled Williams with the Introduction to the list being published on Mapping Mountains in November 2015 and an update relating to the list appearing on Mapping Mountains on the 19th June 2019.
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| The Welsh Highlands - Uchafion Cymru by Myrddyn Phillips and Aled Williams |
The name the hill is listed by is Cwar Blaen Dyffryn, and it is adjoined to the Cefn yr Ystrad group of hills, which are situated in the eastern part of South Wales (Region C, Sub-Region C2), and it is positioned directly above the end of a minor road, and also has the A40 road to its north-east, the A470 road to its west and the A465 road to its south, and has the village of Trefil towards the south-east.
When the two 490m sub categories were added as a part of the Welsh 500m P15s that later became known as Yr Uchafion and latterly as The Welsh Highlands – Uchafion Cymru, this hill was not included as contemporary Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer maps do not give the hill uppermost contours or a spot height.
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| 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 490m Sub-Uchaf status is due to LIDAR analysis, resulting in a 496.0m summit height and a 477.6m bwlch height, with these values giving this hill 18.4m of drop.
The full details for the hill are:
Group: Cefn yr Ystrad
Name: Cwar Blaen Dyffryn
OS 1:50,000 map: 161
Summit Height: 496.0m (LIDAR)
Summit Grid Reference: SO 09829 14840 (LIDAR)
Bwlch Height: 477.6m (LIDAR)
Bwlch Grid Reference: SO 09694 14900 & SO 09698 14902 (LIDAR)
Drop: 18.4m (LIDAR)
For the additions, deletions and reclassifications to The Welsh Highlands – Uchafion Cymru reported on Mapping Mountains please consult the following Change Registers:
Aled Williams and Myrddyn Phillips (November 2020)
Mapping Mountains - Hill Reclassifications - The Welsh Highlands - Uchafion Cymru
Pt. 501.4m (SH 730 397) – Uchaf addition (48th reclassification)
There has been an addition to the listing of The Welsh Highlands – Uchafion Cymru, with the summit height, bwlch height and their locations, the drop and status of the hill confirmed by a Trimble GeoXH 6000 survey conducted by Myrddyn Phillips and Aled Williams on the 19th July 2020 and aerial map comparisons.
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| Pt. 501.4m (SH 730 397) |
The criteria for the list that this addition applies to are:
The Welsh Highlands – Uchafion Cymru – This is the revised draft title for the Welsh 500m P15s list that takes in all hills in Wales at or above 500m in height with 15m minimum drop. The list is co-authored by Myrddyn Phillips and Aled Williams with the Introduction to the list being published on Mapping Mountains in November 2015 and an update relating to the list appearing on Mapping Mountains on the 19th June 2019.
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| The Welsh Highlands - Uchafion Cymru by Myrddyn Phillips and Aled Williams |
For now the hill is being listed by the point (Pt. 501.4m) notation, and it is adjoined to the Arenig Fach group of hills, which are situated in the central part of North Wales (Region A, Sub-Region A3), and it is positioned with the B4391 road to its north, the A470 road to its west and the A4212 road to its south, and has the village of Trawsfynydd towards the south-west.
This hill was not included in the original list of Welsh 500m P15s that later became known as Yr Uchafion and latterly as The Welsh Highlands – Uchafion Cymru, as with a small 500m ring contour and bwlch contouring between 480m – 490m that appear on the Ordnance Survey 1:25,000 Explorer map its interpolated drop value was judged insufficient for either Uchaf or 500m Sub-Uchaf status.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
Since the original compilation of this list there have been a number of Ordnance Survey maps made available online, some of these are historic such as the series of Six-Inch maps on the National Library of Scotland website, whilst others are current and digitally updated such as the mapping on the WalkLakes website and the Magic Maps website.
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| Extract from the WalkLakes website |
One of the mapping resources now available online is the WalkLakes website which hosts an interactive Ordnance Survey map originated from the Ordnance Survey Open Data programme. This map has many spot heights not on other publicly available Ordnance Survey maps and for this hill a 504m spot height is given on the area of its summit.
Another resource available online is the interactive mapping originated from Ordnance Survey data hosted on the Magic Maps website. This mapping also shows a 504m spot height on the summit area of this hill.
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| Extract from the Magic Maps website |
The details for this hill were also re-assessed against the mapping on the OS Maps website. This is the replacement for OS Get-a-map and until recent times had contours at 5m intervals which were proving consistently more accurate compared to the 5m contours that sometimes appear on the Ordnance Survey 1:25,000 Explorer map and used to appear on the online Vector Map Local. This resulted in its bwlch height being estimated as c 488m based on interpolation of 5m contouring between 485m – 490m.
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| Extract from the OS Maps website |
The hill was first proposed as an Uchaf by Myrddyn Phillips and Aled Williams subsequently analysed the hill as follows:
Summit height of c 500m at SH 73026 39780 interpolated from OS paper maps. Bwlch position estimated from QGIS modelling of OS Terrain 50 data to be c 487m at SH 72991 39724. Enlarged-scale online OS maps give a summit height of 504m, which may be the result of a data modelling error caused by the forestry.
However, it was not until the survey with the Trimble GeoXH 6000 that the details for this hill could be accurately re-assessed. The summit of this hill and a number of potential bwlch positions were subsequently surveyed, with the bwlch height and position given for this hill having been obtained from the data spread produced from the various bwlch surveys and scrutiny of aerial map comparisons.
Summit height of c 500m at SH 73026 39780 interpolated from OS paper maps. Bwlch position estimated from QGIS modelling of OS Terrain 50 data to be c 487m at SH 72991 39724. Enlarged-scale online OS maps give a summit height of 504m, which may be the result of a data modelling error caused by the forestry.
However, it was not until the survey with the Trimble GeoXH 6000 that the details for this hill could be accurately re-assessed. The summit of this hill and a number of potential bwlch positions were subsequently surveyed, with the bwlch height and position given for this hill having been obtained from the data spread produced from the various bwlch surveys and scrutiny of aerial map comparisons.
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| At the summit of Pt. 501.4m |
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| Gathering data during one of a number of surveys for the bwlch position of Pt. 501.4m |
Therefore, the addition of this hill to Uchaf status is due to a Trimble GeoXH 6000 survey and aerial map comparisons, resulting in a 501.4m summit height and a 485.5m bwlch height, with these values giving this hill 15.9m of drop, which is sufficient for it to be classified as an Uchaf.
The full details for the hill are:
Group: Arenig Fach
Name: Pt. 501.4m
OS 1:50,000 map: 124
Summit Height: 501.4m (converted to OSGM15, Trimble GeoXH 6000)
Summit Grid Reference: SH 73011 39784 (Trimble GeoXH 6000)
Bwlch Height: 485.5m (Trimble GeoXH 6000 data set spread)
Bwlch Grid Reference: SH 73105 39632 (from aerial map comparisons)
Drop: 15.9m (Trimble GeoXH 6000 summit and Trimble GeoXH 6000 bwlch data set spread)
For the additions, deletions and reclassifications to The Welsh Highlands – Uchafion Cymru reported on Mapping Mountains please consult the following Change Registers:
Myrddyn Phillips and Aled Williams (November 2020)
Mapping Mountains - Hill Reclassifications - The Welsh Highlands - Uchafion Cymru
Pt. 577m (SN 808 768) – 500m Sub-Uchaf addition (47th reclassification)
Pt. 577m (SN 808 768) – 500m Sub-Uchaf addition (47th reclassification)
There has been an addition to the listing of The Welsh Highlands – Uchafion Cymru, 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 Highlands – Uchafion Cymru – This is the revised draft title for the Welsh 500m P15s list that takes in all hills in Wales at or above 500m in height with 15m minimum drop. Accompanying the main list are three sub lists, these are; 500m Sub-Uchaf, 490m Sub-Uchaf and the Double Sub category, with this hill being added as a 500m Sub-Uchaf. The criteria for which are all Welsh hills at or above 500m in height with 14m or more and below 15m of drop. The list is co-authored by Myrddyn Phillips and Aled Williams with the Introduction to the list being published on Mapping Mountains in November 2015 and an update relating to the list appearing on Mapping Mountains on the 19th June 2019.
As the authors do not know an appropriate name for the hill either from historic research or from local enquiry it is being listed by the point (Pt. 577m) notation, and it is adjoined to the Elenydd group of hills, which are situated in the northern part of Mid and West Wales (Region B, Sub-Region B2), and it is positioned with the A44 road to its north, the A4120 road to its west, the B4574 road to its south-west, a minor road to its south and the A470 road to its east, and has the village of Pontarfynach (Devil’s Bridge) towards the west.
This hill was not included as a P14 Sub in the original list of Welsh 500m P15s that later became known as Yr Uchafion and latterly as The Welsh Highlands – Uchafion Cymru, as with a 577m summit spot height and bwlch contouring between 560m – 570m that appear on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map its interpolated drop value was judged insufficient for 500m Sub-Uchaf status.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
Since the original compilation of this list there are now a number of interactive maps originated from Ordnance Survey data that are available online. One of these is the mapping on the OS Maps website. This is the replacement for OS Get-a-map and has contours at 5m intervals which are proving consistently more accurate compared to the 5m contours that sometimes appear on Ordnance Survey 1:25,000 Explorer maps and used to appear on the online Vector Map Local. This mapping has bwlch contouring between 560m – 565m, with interpolation giving an estimated bwlch height of c 563m.
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| Extract from the OS Maps website |
Therefore, the addition of this hill to 500m Sub-Uchaf status is due to detail on contemporary maps produced from Ordnance Survey data, resulting in a 577m summit height and an estimated c 563m bwlch height, with these values giving this hill c 14m of drop, which is sufficient for it to be classified as a 500m Sub-Uchaf.
The full details for the hill are:
Group: Elenydd
Name: Pt. 577m
OS 1:50,000 map: 135, 136, 147
Summit Height: 577m (spot height)
Summit Grid Reference: SN 80889 76890 (spot height)
Bwlch Height: c 563m (interpolation)
Bwlch Grid Reference: SN 80536 77083 (interpolation)
Drop: c 14m (spot height summit and interpolated bwlch)
For the additions, deletions and reclassifications to The Welsh Highlands – Uchafion Cymru reported on Mapping Mountains please consult the following Change Registers:
Aled Williams and Myrddyn Phillips (August 2020)
Mapping Mountains - Hill Reclassifications - The Welsh Highlands - Uchafion Cymru
Pt. 522.2m (SJ 136 363) – 500m Sub-Uchaf addition (46th reclassification)
There has been an addition to the listing of The Welsh Highlands – Uchafion Cymru, with the summit height, bwlch height and their locations, the drop and status of the hill confirmed by 1m DSM LIDAR analysis conducted by Aled Williams.
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| LIDAR image of Pt. 522.2m (SJ 136 363) |
The criteria for the list that this addition applies to are:
The Welsh Highlands – Uchafion Cymru – This is the revised draft title for the Welsh 500m P15s list that takes in all hills in Wales at or above 500m in height with 15m minimum drop. Accompanying the main list are three sub lists, these are; 500m Sub-Uchaf, 490m Sub-Uchaf and the Double Sub category, with this hill being added as a 500m Sub-Uchaf. The criteria for which are all Welsh hills at or above 500m in height with 14m or more and below 15m of drop. The list is co-authored by Myrddyn Phillips and Aled Williams with the Introduction to the list being published on Mapping Mountains in November 2015 and an update relating to the list appearing on Mapping Mountains on the 19th June 2019.
For now, the hill is being listed by the point (Pt. 522.2m) notation, and it is adjoined to the Y Berwyn group of hills, which are situated in the south-eastern part of North Wales (Region A, Sub-Region A4), and it is positioned with the A5 road to its north, the B4401 road to its west and the B4500 road to east, and has the town of Llangollen towards the north-east.
This hill was included as a P14 Sub in the original list of Welsh 500m P15s that later became known as Yr Uchafion and latterly as The Welsh Highlands – Uchafion Cymru, as with a 522m summit spot height and a 508m bwlch spot height that appear on the Ordnance Survey 1:25,000 Explorer map, these values gave this hill 14m of drop.
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| 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.
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| LIDAR bwlch image of Pt. 522.2m (SJ 136 363) |
The hill was subsequently deleted from 500m Sub-Uchaf status based on DTM LIDAR analysis conducted by Aled Williams resulting in a 522.0m summit height and a 508.2m bwlch height, with these values giving this hill 13.8m of drop.
The details of this hill have now been re-assessed using the 1m DSM LIDAR model by Aled Williams resulting in a 522.2m summit height and a 508.2m bwlch height, with these values giving this hill 14.0m of drop, which is sufficient for it to be re-instated to 500m Sub-Uchaf status.
The full details for the hill are:
Group: Y Berwyn
Name: Pt. 522.2m
OS 1:50,000 map: 125
Summit Height: 522.2m (LIDAR)
Summit Grid Reference: SJ 13614 36370 (LIDAR)
Bwlch Height: 508.2m (LIDAR)
Bwlch Grid Reference: SJ 13888 36062 (LIDAR)
Drop: 14.0m (LIDAR)
For the additions, deletions and reclassifications to The Welsh Highlands – Uchafion Cymru reported on Mapping Mountains please consult the following Change Registers:
Aled Williams and Myrddyn Phillips (August 2020)
Mapping Mountains - Hill Reclassifications - The Welsh Highlands - Uchafion Cymru
DUE TO SUBSEQUENT LIDAR ANALYSIS THIS HILL HAS BEEN RECLASSIFIED FROM WELSH HIGHLAND SUB STATUS TO WELSH HIGHLAND P15 STATUS
Pt. 576m (SH 559 475) – 500m Sub-Uchaf addition (45th reclassification)
There has been an addition to the listing of The Welsh Highlands – Uchafion Cymru, 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 Highlands – Uchafion Cymru – This is the revised draft title for the Welsh 500m P15s list that takes in all hills in Wales at or above 500m in height with 15m minimum drop. Accompanying the main list are three sub lists, these are; 500m Sub-Uchaf, 490m Sub-Uchaf and the Double Sub category, with this hill being added as a 500m Sub-Uchaf. The criteria for which are all Welsh hills at or above 500m in height with 14m or more and below 15m of drop. The list is co-authored by Myrddyn Phillips and Aled Williams with the Introduction to the list being published on Mapping Mountains in November 2015 and an update relating to the list appearing on Mapping Mountains on the 19th June 2019.
As the authors do not know an appropriate name for the hill either from historic research or from local enquiry it is being listed by the point (Pt. 576m) notation, 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 B4418 road to its north, the A487 road to its west and the A4085 road to its north-east, and has the village of Beddgelert towards the east.
This hill was not included as a P14 Sub in the original list of Welsh 500m P15s that later became known as Yr Uchafion and latterly as The Welsh Highlands – Uchafion Cymru, as with no separate uppermost ring contour there was no map evidence to suggest that any form of hill with qualifying prominence existed.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
Since the original compilation of this list there are now a number of interactive maps originated from Ordnance Survey data that are available online. One of these is the mapping on the Magic Maps website, and this map gives this hill a summit spot height of 576m which is positioned at SH 55928 47522.
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| Extract from the Magic Maps website |
Another resource 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 Ordnance Survey maps and for this hill it also shows the 576m summit spot height.
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| Extract from the WalkLakes website |
The details for this hill were also re-examined against the Ordnance Survey non-contour Vector Map Local hosted on the Geograph website and which is entitled the Interactive Coverage Map. This is another map that has many spot heights that do not appear on other publicly available Ordnance Survey maps and it also gives a 576m summit spot height.
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| Extract from the Ordnance Survey non-contour Vector Map Local hosted on the Geograph website |
The details for this hill were also re-assessed when the OS Maps website became available online. This is the replacement for OS Get-a-map and has contours at 5m intervals which are proving consistently more accurate compared to the 5m contours that sometimes appear on Ordnance Survey 1:25,000 Explorer maps and used to appear on the online Vector Map Local. This mapping has bwlch contouring between 560m – 565m, with interpolation giving an estimated bwlch height of c 562m.
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| Extract from the OS Maps website |
Therefore, the addition of this hill to 500m Sub-Uchaf status is due to detail on contemporary maps produced from Ordnance Survey data, resulting in a 576m summit height and an estimated c 562m bwlch height, with these values giving this hill c 14m of drop, which is sufficient for it to be classified as a 500m Sub-Uchaf.
The full details for the hill are:
Group: Moel Hebog
Name: Pt. 576m
OS 1:50,000 map: 115
Summit Height: 576m (spot height)
Summit Grid Reference: SH 55928 47522 (spot height)
Bwlch Height: c 562m (interpolation)
Bwlch Grid Reference: SH 55895 47581 (interpolation)
Drop: c 14m (spot height summit and interpolated bwlch)
For the additions, deletions and reclassifications to The Welsh Highlands – Uchafion Cymru reported on Mapping Mountains please consult the following Change Registers:
Aled Williams and Myrddyn Phillips (July 2020)
Mapping Mountains - Hill Reclassifications - The Welsh Highlands - Uchafion Cymru
Pt. 582m (SJ 086 373) – 500m Sub-Uchaf addition (44th reclassification)
There has been an addition to the listing of The Welsh Highlands – Uchafion Cymru, 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 Highlands – Uchafion Cymru – This is the revised draft title for the Welsh 500m P15s list that takes in all hills in Wales at or above 500m in height with 15m minimum drop. Accompanying the main list are three sub lists, these are; 500m Sub-Uchaf, 490m Sub-Uchaf and the Double Sub category, with this hill being added as a 500m Sub-Uchaf. The criteria for which are all Welsh hills at or above 500m in height with 14m or more and below 15m of drop. The list is co-authored by Myrddyn Phillips and Aled Williams with the Introduction to the list being published on Mapping Mountains in November 2015 and an update relating to the list appearing on Mapping Mountains on the 19th June 2019.
As the authors do not know an appropriate name for the hill either from historic research or from local enquiry it is being listed by the point (Pt. 582m) notation, and it is adjoined to the Y Berwyn group of hills, which are situated in the south-eastern part of North Wales (Region A, Sub-Region A4), and it is positioned with the A5 road to its north, the B4401 road to its west and the B4391 road to its south-west, and has the village of Cynwyd towards the north-west.
This hill was not included as a P14 Sub in the original list of Welsh 500m P15s that later became known as Yr Uchafion and latterly as The Welsh Highlands – Uchafion Cymru, as with a 582m summit spot height and bwlch contouring between 570m – 580m that appear on the Ordnance Survey 1:25,000 Explorer map, this contouring implied that the hill did not have sufficient drop to be considered for P14 500m Sub-Uchaf status.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
Since the original compilation of this list there are now a number of interactive maps originated from Ordnance Survey data that are available online. One of these is the mapping on the OS Maps website. This is the replacement for OS Get-a-map and has contours at 5m intervals which are proving consistently more accurate compared to the 5m contours that sometimes appear on Ordnance Survey 1:25,000 Explorer map and used to appear on the online Vector Map Local. This mapping has an uppermost 580m ring contour and bwlch contouring between 565m – 570m, with interpolation giving an estimated bwlch height of c 568m.
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| Extract from the OS Maps website |
Therefore, the addition of this hill to 500m Sub-Uchaf status is due to detail on contemporary maps produced from Ordnance Survey data, resulting in a 582m summit height and an estimated c 568m bwlch height, with these values giving this hill c 14m of drop, which is sufficient for it to be classified as a 500m Sub-Uchaf.
The full details for the hill are:
Group: Y Berwyn
Name: Pt. 582m
OS 1:50,000 map: 125
Summit Height: 582m (spot height)
Summit Grid Reference: SJ 08663 37377 (spot height)
Bwlch Height: c 568m (interpolation)
Bwlch Grid Reference: SJ 08668 37312 (interpolation)
Drop: c 14m (spot height summit and interpolated bwlch)
For the additions, deletions and reclassifications to The Welsh Highlands – Uchafion Cymru reported on Mapping Mountains please consult the following Change Registers:
Myrddyn Phillips and Aled Williams (July 2020)
Mapping Mountains - Hill Reclassifications - The Welsh Highlands - Uchafion Cymru
Iwerddon (SH 686 479) – Uchaf addition (43rd reclassification)
There has been an addition to the listing of The Welsh Highlands – Uchafion Cymru, 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.
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| Iwerddon (SH 686 479) |
The criteria for the list that this addition applies to are:
The Welsh Highlands – Uchafion Cymru – This is the revised draft title for the Welsh 500m P15s list that takes in all hills in Wales at or above 500m in height with 15m minimum drop. Accompanying the main list are three sub lists, these are; 500m Sub-Uchaf, 490m Sub-Uchaf and the Double Sub category. The list is co-authored by Myrddyn Phillips and Aled Williams with the Introduction to the list being published on Mapping Mountains in November 2015 and an update relating to the list appearing on Mapping Mountains on the 19th June 2019.
The name the hill is listed by is Iwerddon and it is adjoined to the Moelwynion 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 and the A496 roads to its south and the A470 road to its east, and has the town of Blaenau Ffestiniog towards the south-east.
This hill was not included in the original list of Welsh 500m P15s that later became known as Yr Uchafion and latterly as The Welsh Highlands – Uchafion Cymru, as with a 570m uppermost ring contour and no summit spot height and bwlch contouring between 560m – 570m that appear on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map, it was difficult through interpolation to give this hill an estimated drop value.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
Since the original compilation of this list there are now a number of interactive maps originated from Ordnance Survey data that are available online. One of these is the mapping on the Magic Maps website, and this map gives this hill a summit spot height of 579m which is positioned at SH 68671 47997.
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| Extract from the Magic Maps website |
Another resource 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 Ordnance Survey maps and for this hill it also shows the 579m summit spot height.
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| Extract from the WalkLakes website |
The details for this hill were re-examined when the Ordnance Survey Vector Map Local hosted on the Geograph website and which is entitled the Interactive Coverage Map became available online. This mapping had many spot heights not on any other publicly available Ordnance Survey map and its non-contour map also gives a 579m summit spot height.
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| Extract from the Ordnance Survey non-contour Vector Map Local hosted on the Geograph website |
The details for this hill were also re-assessed when the OS Maps website became available online. This is the replacement for OS Get-a-map and has contours at 5m intervals which are proving consistently more accurate compared to the 5m contours that sometimes appear on Ordnance Survey 1:25,000 Explorer maps and used to appear on the online Vector Map Local. This mapping has an uppermost 575m ring contour and bwlch contouring between 560m – 565m, with interpolation giving an estimated bwlch height of c 564m.
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| Extract from the OS Maps website |
Therefore, the addition of Iwerddon to Uchaf status is due to detail on contemporary maps produced from Ordnance Survey data, resulting in a 579m summit height and an estimated c 564m bwlch height, with these values giving this hill c 15m of drop, which is sufficient for it to be classified as an Uchaf.
The full details for the hill are:
Group: Moelwynion
Name: Iwerddon
OS 1:50,000 map: 115
Summit Height: 579m (spot height)
Summit Grid Reference: SH 68671 47997 (spot height)
Bwlch Height: c 564m (interpolation)
Bwlch Grid Reference: SH 68738 48072 (interpolation)
Drop: c 15m (spot height summit and interpolated bwlch)
For the additions, deletions and reclassifications to The Welsh Highlands – Uchafion Cymru reported on Mapping Mountains please consult the following Change Registers:
Myrddyn Phillips and Aled Williams (July 2020)
Mapping Mountains - Hill Reclassifications - The Welsh Highlands - Uchafion Cymru
Waun Goch (SN 841 943) – 500m Sub-Uchaf deletion (42nd reclassification)
There has been a deletion to the listing of The Welsh Highlands – Uchafion Cymru, with the summit height, bwlch height and their locations, the drop and status of the hill confirmed by a Trimble GeoXH 6000 survey conducted by Myrddyn Phillips on the 5th May 2016.
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| Waun Goch (SN 841 943) |
The criteria for the list that this deletion applies to are:
The Welsh Highlands – Uchafion Cymru – This is the revised draft title for the Welsh 500m P15s list that takes in all hills in Wales at or above 500m in height with 15m minimum drop. Accompanying the main list are three sub lists, these are; 500m Sub-Uchaf, 490m Sub-Uchaf and the Double Sub category, with this hill being deleted from the 500m Sub-Uchaf category. The criteria for which are all Welsh hills at or above 500m in height with 14m or more and below 15m of drop. The list is co-authored by Myrddyn Phillips and Aled Williams with the Introduction to the list being published on Mapping Mountains in November 2015 and an update relating to the list appearing on Mapping Mountains on the 19th June 2019.
The name the hill is listed by is Waun Goch 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 a minor road to its north and the B4518 to its east, and has the small community of Dylife towards the east.
This hill was not included as a P14 Sub in the original list of Welsh 500m P15s that later became known as Yr Uchafion and latterly as The Welsh Highlands – Uchafion Cymru, as with a c 520m summit height and bwlch contouring between 500m – 510m that appear on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map, interpolation suggested that it did not have sufficient drop to be considered for P14 500m Sub-Uchaf status.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
This hill was subsequently surveyed using a basic levelling staff on the 22nd May 2004 by Myrddyn Phillips, resulting in a 46ft / 14.0m drop value, which was sufficient for it to be classified as a 500m Sub-Uchaf.
However, as the margin of uncertainty applicable to the basic levelling method of surveying over the distance between bwlch and summit of this hill is approximately +/- 1.5m, the hill was prioritised for an accurate GNSS survey.
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| The Trimble GeoXH 6000 gathering data at the summit of Waun Goch |
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| The Trimble GeoXH 6000 gathering data at the bwlch of Waun Goch |
Therefore, the deletion of Waun Goch from 500m Sub-Uchaf status is due to a survey with the Trimble GeoXH 6000, resulting in a 520.8m summit height and a 508.3m bwlch height, with these values giving this hill 12.5m of drop which is insufficient for it to be retained as a 500m Sub-Uchaf.
The full details for the hill are:
Group: Pumlumon
Name: Waun Goch
OS 1:50,000 map: 135, 136
Summit Height: 520.8m (converted to OSGM15)
Summit Grid Reference: SN 84142 94373
Bwlch Height: 508.3m (converted to OSGM15)
Bwlch Grid Reference: SN 84324 94975
Drop: 12.5m
For the additions, deletions and reclassifications to The Welsh Highlands – Uchafion Cymru reported on Mapping Mountains please consult the following Change Registers:
Aled Williams and Myrddyn Phillips (July 2020)
Carreg Gwalch (SH 642 552) – Welsh Highland Sub addition (41st reclassification)
There has been an addition to the listing of The Welsh Highlands – Uchafion Cymru, 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 confirmed by subsequent LIDAR analysis and a Trimble GeoXH 6000 survey conducted by Aled Williams.
%20-%20LIDAR%20hill%202.jpg) |
| LIDAR image of Carreg Gwalch (SH 642 552) |
%20-%20hill%201.JPG) |
| Carreg Gwalch (SH 642 552). Photo: Aled Williams |
The criteria for the list that this addition applies to are:
Welsh Highlands – Uchafion Cymru – Welsh hills at or above 500m in height with 15m minimum drop, with an accompanying sub list entitled the Welsh Highland Subs, the criteria for which is all Welsh hills at or above 500m in height with 10m or more and below 15m of drop. This list is authored by Myrddyn Phillips and Aled Williams with the Introduction to the list published on Mapping Mountains in November 2015 and the latest update relating to the list published on Mapping Mountains in January 2023.
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| Welsh Highlands - Uchafion Cymru by Myrddyn Phillips and Aled Williams |
The name the hill is listed by is Carreg Gwalch and it is adjoined to the Yr Wyddfa 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 A4086 road to its north and the A498 to its south-east, and has the village of Capel Curig towards the east north-east.
This hill was not included as a P14 Sub in the original list of Welsh 500m P15s that later became known as Yr Uchafion and latterly as The Welsh Highlands – Uchafion Cymru, as with a 545m summit spot height and bwlch contouring between 530m – 540m that appear on the Ordnance Survey 1:25,000 Explorer map, interpolation suggested that it did not have sufficient drop to be considered for P14 500m Sub-Uchaf status.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
Since the original compilation of this list there are now a number of interactive maps originated from Ordnance Survey data that are available online. One of these is available on the Magic Maps website, and it is this map that gives this hill a summit spot height of 546m.
 |
| Extract from the Magic Maps website |
Another resource 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 Ordnance Survey maps and for this hill it also shows a 546m summit spot height which is positioned at SH 64236 55249.
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| Extract from the WalkLakes website |
The details for this hill were also re-assessed when the OS Maps website became available online. This is the replacement for OS Get-a-map and has contours at 5m intervals which are proving consistently more accurate compared to the 5m contours that sometimes appear on Ordnance Survey 1:25,000 Explorer maps and used to appear on the online Vector Map Local. This mapping has an uppermost 545m ring contour and bwlch contouring between 530m – 535m, with interpolation giving an estimated bwlch height of c 532m.
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| Extract from the OS Maps website |
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. As this hill has now been surveyed with the Trimble GeoXH 6000, it is this result that is being prioritised.
%20-%20summit%20survey.JPG) |
| Gathering data at the summit of Carreg Gwalch (SH 642 552). Photo: Aled Williams |
%20-%20bwlch%20survey.JPG) |
| Gathering data at the bwlch of Carreg Gwalch (summit at SH 642 552). Photo: Aled Williams |
Therefore, the addition of this hill to Welsh Highland Sub status is due to detail on contemporary maps produced from Ordnance Survey data, and its status confirmed from subsequent LIDAR analysis and a Trimble GeoXH 6000 survey, resulting in a 546.0m summit height and a 531.2m bwlch height, with these values giving this hill 14.7m of drop, which is sufficient for it to be classified as a Welsh Highland Sub.
The full details for the hill are:
Group: Yr Wyddfa
Name: Carreg Gwalch
OS 1:50,000 map: 115
Summit Height: 546.0m (converted to OSGM15)
Summit Grid Reference: SH 64238 55249
Bwlch Height: 531.2m (converted to OSGM15)
Bwlch Grid Reference: SH 64229 55166
Drop: 14.7m
For the additions, deletions and reclassifications to The Welsh Highlands – Uchafion Cymru reported on Mapping Mountains please consult the following Change Registers:
Aled Williams and Myrddyn Phillips (July 2020)
Mapping Mountains - Hill Reclassifications - The Welsh 500m P15s (Yr Uchafion)
Moel Darren (SH 952 413) – Uchaf reclassified to 500m Sub-Uchaf (40th reclassification)
There has been a reclassification to the listing of The Welsh Highlands – Uchafion Cymru due to a Trimble GeoXH 6000 survey conducted by Myrddyn Phillips and Aled Williams on the 19th January 2020.
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| Moel Darren (SH 952 413) |
The criteria for the list that this reclassification applies to are:
The Welsh Highlands – Uchafion Cymru – This is the revised draft title for the Welsh 500m P15s list that takes in all hills in Wales at or above 500m in height with 15m minimum drop. Accompanying the main list are three sub lists, these are; 500m Sub-Uchaf, 490m Sub-Uchaf and the Double Sub category, with this hill being reclassified to 500m Sub-Uchaf status, the criteria for which are all Welsh hills at or above 500m in height with 14m or more and below 15m of drop. The list is co-authored by Myrddyn Phillips and Aled Williams with the Introduction to the list being published on Mapping Mountains in November 2015 and an update relating to the list appearing on Mapping Mountains on the 19th June 2019.
The name the hill is listed by is Moel Darren 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 the A5 road to its north-east, the B4501 road to its west and the A494 road to its south-east, and has the town of Y Bala towards the south south-west and the village of Cerrigydrudion towards the north.
This hill was not included in the original list of Welsh 500m P15s that later became known as Yr Uchafion and latterly as The Welsh Highlands – Uchafion Cymru, however it was listed as a potential qualifying hill as it has a 509m summit spot height on contemporary Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer maps and bwlch contouring between 490m – 500m.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
This hill was subsequently surveyed using a basic levelling staff on the 1st May 2004 by Myrddyn Phillips, resulting in a 51½ft / 15.7m drop value, which was sufficient for it to be classified as an Uchaf.
However, as the margin of uncertainty applicable to the basic levelling method of surveying over the distance between bwlch and summit and the terrain of this hill is approximately +/- 1m, the hill was prioritised for an accurate survey.
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| The Trimble GeoXH 6000 gathering data at the summit of Moel Darren |
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| The Trimble GeoXH 6000 gathering data at the bwlch of Moel Darren |
Therefore, the reclassification of Moel Darren to 500m Sub-Uchaf status is due to a survey with the Trimble GeoXH 6000, resulting in a 510.0m summit height and a 495.4m bwlch height, with these values giving this hill 14.6m of drop which is insufficient for it to be retained as an Uchaf.
The full details for the hill are:
Group: Arenig
Name: Moel Darren
OS 1:50,000 map: 125
Summit Height: 510.0m (converted to OSGM15)
Summit Grid Reference: SH 95221 41372
Bwlch Height: 495.4m (converted to OSGM15)
Bwlch Grid Reference: SH 95185 41686
Drop: 14.6m
For the additions, deletions and reclassifications to The Welsh Highlands – Uchafion Cymru reported on Mapping Mountains please consult the following Change Registers:
Aled Williams and Myrddyn Phillips (June 2020)
Twynau Gwynion (SO 067 107) – Double Sub-Uchaf reclassified to 490m Sub-Uchaf (39th reclassification)
There has been a reclassification to the listing of The Welsh Highlands – Uchafion Cymru, with the summit height, bwlch height and their locations, the drop and status of the hill confirmed by 2m DSM LIDAR analysis conducted by Aled Williams.
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| LIDAR image of Twynau Gwynion (SO 067 107) |
The criteria for the list that this reclassification applies to are:
The Welsh Highlands – Uchafion Cymru – This is the revised draft title for the Welsh 500m P15s list that takes in all hills in Wales at or above 500m in height with 15m minimum drop. Accompanying the main list are three sub lists, these are; 500m Sub-Uchaf, 490m Sub-Uchaf and the Double Sub category, with this hill being reclassified from Double Sub status to 490m Sub-Uchaf status. The criteria for Double Sub status are all Welsh hills at or above 490m in height and below 500m in height that have 14m or more and below 15m of drop, with the criteria for 490m Sub-Uchaf status being all Welsh hills at or above 490m in height and below 500m in height that have 15m minimum drop. The list is co-authored by Myrddyn Phillips and Aled Williams with the Introductionto the list being published on Mapping Mountains in November 2015 and an update relating to the list appearing on Mapping Mountains on the 19th June 2019.
The name the hill is listed by is Twynau Gwynion and it is adjoined to the Cymoedd Gwent group of hills, which are situated in the eastern part of South Wales (Region C, Sub-Region C2), and is positioned with the A470 road to its west and the A465 road to its south, and has the town of Merthyr Tudful towards the south.
When the two 490m sub categories were included as a part of this list this hill was listed with 16m of drop based on a 498m summit height that appears as a spot height on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer maps and a 482m bwlch height that appeared as a spot height on the Ordnance Survey Vector Map Local hosted on the Geograph website and which is entitled the Interactive Coverage Map.
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| 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 hill was subsequently reclassified from 490m Sub-Uchaf status to Double Sub-Uchaf status based on DTM LIDAR analysis conducted by Aled Williams resulting in a 496.2m summit height and a 481.3m bwlch height, with these values giving this hill 14.9m of drop.
The details of this hill have now been re-assessed using the 2m DSM LIDAR model initially by Aled Williams and subsequently by Myrddyn Phillips, resulting in a 496.8m summit height and a 481.4m bwlch height, with these values giving this hill 15.5m of drop, which is sufficient for it to be re-instated to 490m Sub-Uchaf status.
The full details for the hill are:
Group: Cymoedd Gwent
Name: Twynau Gwynion
OS 1:50,000 map: 160
Summit Height: 496.8m (LIDAR)
Summit Grid Reference: SO 06765 10701 (LIDAR)
Bwlch Height: 481.4m (LIDAR)
Bwlch Grid Reference: SO 06779 10861 (LIDAR)
Drop: 15.5m (LIDAR)
For the additions, deletions and reclassifications to The Welsh Highlands – Uchafion Cymru reported on Mapping Mountains please consult the following Change Registers:
Aled Williams and Myrddyn Phillips (February 2020)
Mapping Mountains - Hill Reclassifications - The Welsh 500m P15s (Yr Uchafion)
Clo Cadno (SO 118 162) – Welsh Highland P15 addition (38th reclassification)
There has been an addition to the listing of the Welsh Highlands – Uchafion Cymru, with the summit height, bwlch height and their locations, the drop and status of the hill derived from LIDAR analysis conducted by Aled Williams.
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| LIDAR image of Clo Cadno (SO 118 162) |
The criteria for the list that this addition applies to are:
The Welsh Highlands – Uchafion Cymru – This is the revised draft title for the Welsh 500m P15s list that takes in all hills in Wales at or above 500m in height with 15m minimum drop. The list is co-authored by Myrddyn Phillips and Aled Williams with the Introduction to the list being published on Mapping Mountains in November 2015 and an update relating to the list appearing on Mapping Mountains on the 19th June 2019.
The name the hill is listed by is Clo Cadno and it is adjoined to the Cymoedd Gwent group of hills, which are situated in the eastern part of South Wales (Region C, Sub-Region C2), and is positioned with minor roads to its north-west and south-west and the B4560 road to its east, and has the village of Llangynidr towards the north-east and the small community of Trefil towards the south.
During the compilation of the original list of Welsh 500m P15s that later became known as Yr Uchafion and latterly as the Welsh Highlands – Uchafion Cymru, this hill was not included in the main P15 list as Ordnance Survey 1:25,000 Explorer maps only give an uppermost 520m ring contour with bwlch contouring between 510m – 520m.
 |
| Extract from the Ordnance Survey 1:25,000 Explorer map |
The details for this hill were re-examined via mapping on the OS Maps website. This is the replacement for OS Get-a-map and has contours at 5m intervals which are proving consistently more accurate compared to the 5m contours that sometimes appear on Ordnance Survey 1:25,000 Explorer maps and the online Vector Map Local hosted on the Geograph website. As OS Maps data suggested that this hill had a minimum of 15m of drop it prompted scrutiny using LIDAR.
 |
| Extract from the OS Maps website |
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 Clo Cadno to Welsh Highland P15 status is due to LIDAR analysis, resulting in a 530.3m summit height and a 513.6m bwlch height, with these values giving this hill 16.7m of drop which is sufficient for it to be classified as a Welsh Highland P15.
The full details for the hill are:
Group: Cymoedd Gwent
Name: Clo Cadno
OS 1:50,000 map: 161
Summit Height: 530.3m (LIDAR)
Summit Grid Reference: SO 11849 16247 (LIDAR)
Bwlch Height: 513.6m (LIDAR)
Bwlch Grid Reference: SO 12197 15992 (LIDAR)
Drop: 16.7m (LIDAR)
For the additions, deletions and reclassifications to The Welsh Highlands – Uchafion Cymru reported on Mapping Mountains please consult the following Change Registers:
Aled Williams and Myrddyn Phillips (January 2020)
Clogwyn Drain (SH 652 493) – Uchaf addition (37th reclassification)
There has been an addition to the listing of The Welsh Highlands – Uchafion Cymru due to analysis of 5m contouring on the OS Maps website coupled with spot height data on the contemporary Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map.
The criteria for the list that this addition applies to are:
The Welsh Highlands – Uchafion Cymru – This is the revised draft title for the Welsh 500m P15s list that takes in all hills in Wales at or above 500m in height with 15m minimum drop. The list is co-authored by Myrddyn Phillips and Aled Williams with the introduction to the list being published on Mapping Mountains in November 2015 and an update relating to the list appearing on Mapping Mountains on the 19th June 2019.
The name of the hill is Clogwyn Drain and it is adjoined to the Moelwynion group of hills, which are situated in the north-western part of North Wales (Region A, Sub-Region A1), and is positioned with the A498 road to its north-west and the A470 road to its east, and has the village of Beddgelert towards the west south-west and the town of Blaenau Ffestiniog towards the south-east.
During the initial compilation of the original list of Welsh 500m P15s that later became known as Yr Uchafion and latterly as The Welsh Highlands – Uchafion Cymru, this hill was included as an Uchaf with 19m of drop based on a basic levelling survey conducted by Myrddyn Phillips on the 25th May 2004.
However, this survey was conducted at the end of a long day on the hill which involved many such surveys and as contemporary Ordnance Survey maps of the day gave a 508m summit spot height and bwlch contouring between 490m – 500m, it meant that if this survey and the summit spot height were accurate the height of the bwlch would be below that of its lower 490m contour. Because of this the survey result was questioned and the hill taken out of the list.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
The details for this hill were re-examined when the Ordnance Survey Vector Map Local hosted on the Geograph website and which is entitled the Interactive Coverage Map became available online. This mapping has many spot heights not on any other publicly available Ordnance Survey map and gives a 498m spot height positioned at SH 65212 49275 on the bwlch area of this hill. This spot height is also shown on Ordnance Survey data that appears on the Magic Maps website. When coupled with the 508m summit spot height these values gave this hill 10m of drop and the questionable accuracy of the basic levelling survey seemed to be substantiated.
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| Extract from the Magic Maps website |
The details for this hill were re-assessed when the OS Maps website became available online. This is the replacement for OS Get-a-map and has contours at 5m intervals which are proving consistently more accurate compared to the 5m contours that sometimes appear on Ordnance Survey 1:25,000 Explorer maps and the online Vector Map Local. This mapping has an uppermost 505m contour and bwlch contouring between 490m – 495m and places the position of the 498m spot height above the 495m contour line, indicating that the spot height is not placed at the critical point of the bwlch. This re-assessment resulted in the hill being listed with an estimated c 15m of drop.
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| Extract from OS Maps |
Therefore, the addition of this hill to Uchaf status is due to the 508m summit spot height that appears on contemporary 1:50,000 Landranger and 1:25,000 Explorer maps and an estimated bwlch height of c 493m based on 5m contouring on the OS Maps website between 490m – 495m, with these values giving this hill c 15m of drop which is sufficient for Uchaf status.
The full details for the hill are:
Group: Moelwynion
Name: Clogwyn Drain
OS 1:50,000 map: 115
Summit Height: 508m (spot height)
Summit Grid Reference: SH 65200 49356 (spot height)
Bwlch Height: c 493m (interpolation)
Bwlch Grid Reference: SH 65239 49257 (interpolation)
Drop: c 15m (spot height summit and interpolated bwlch)
For the additions, deletions and reclassifications to The Welsh Highlands – Uchafion Cymru reported on Mapping Mountains please consult the following Change Registers:
Aled Williams and Myrddyn Phillips (January 2020)
Mapping Mountains - Hill Reclassifications - The Welsh 500m P15s (Yr Uchafion)
Llechwedd Du (SH 893 446) – 500m Sub-Uchaf reclassified to Uchaf (36th reclassification)
THIS HILL HAS SUBSEQUENTLY BEEN RECLASSIFIED TO WELSH HIGHLAND SUB STATUS
There has been a reclassification to the listing of The Welsh Highlands – Uchafion Cymru due to analysis of 5m contouring on the OS Maps website coupled with spot height data on the contemporary Ordnance Survey 1:25,000 Explorer map.
The criteria for the list that this reclassification applies to are:
The Welsh Highlands – Uchafion Cymru – This is the revised draft title for the Welsh 500m P15s list that takes in all hills in Wales at or above 500m in height with 15m minimum drop. Accompanying the main list are three sub lists, these are; 500m Sub-Uchaf, 490m Sub-Uchaf and the Double Sub category, with this hill being reclassified from 500m Sub-Uchaf status, the criteria for which are all Welsh hills at or above 500m in height with 14m or more and below 15m of drop. The list is co-authored by Myrddyn Phillips and Aled Williams with the Introduction to the list being published on Mapping Mountains in November 2015 and an update relating to the list appearing on Mapping Mountains on the 19th June 2019.
The name of the hill is Llechwedd Du 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 is positioned with the A4212 road to its south, and the B4501 road to its east, and has the town of Y Bala towards its south south-east and the village of Cerrigydrudion towards the north-east.
When the original list of Welsh 500m P15s that later became known as Yr Uchafion and latterly as The Welsh Highlands – Uchafion Cymru was compiled, this hill was included as a 500m Sub-Uchaf with 14m of drop based on the 509m summit spot height that appears on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map and the 495m bwlch spot height that appears on the Ordnance Survey 1:25,000 Explorer map.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
The details for this hill were re-assessed when the OS Maps website became available online. This is the replacement for OS Get-a-map and has contours at 5m intervals which are proving consistently more accurate compared to the 5m contours that sometimes appear on Ordnance Survey 1:25,000 Explorer maps and the online Vector Map Local. This re-assessment resulted in the hill being listed with c 16m of drop based on an estimated summit height of c 511m from interpolation of the 510m uppermost contour and the 495m bwlch spot height that appears on the Ordnance Survey 1:25,000 Explorer map.
 |
| Extract from the OS Maps website |
Therefore, the reclassification of this hill from 500m Sub-Uchaf to Uchaf status is due to an estimated summit height of c 511m based on the 5m contours on the OS Maps website and the 495m bwlch spot height that appears on the Ordnance Survey 1:25,000 Explorer map, with these values giving this hill c 16m of drop, which is sufficient for it to be reclassified to Uchaf status.
The full details for the hill are:
Group: Arenig
Name: Llechwedd Du
OS 1:50,000 map: 124, 125
Summit Height: c 511 (interpolation)
Summit Grid Reference: SH 89377 44652 (spot height)
Bwlch Height: 495m (spot height)
Bwlch Grid Reference: SH 89128 44308 (spot height)
Drop: c 16m
For the additions, deletions and reclassifications to The Welsh Highlands – Uchafion Cymru reported on Mapping Mountains please consult the following Change Registers:
Aled Williams and Myrddyn Phillips (December 2019)
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