Mapping Mountains - Hill Reclassifications - Welsh Highlands - Uchafion Cymru
Clipiau Duon (SH 900 227) – Welsh Highland Sub addition (112th 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 Clipiau Duon (SH 900 227) |
The criteria for the list that this addition applies to are:
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Welsh Highlands - Uchafion Cymru by Aled Williams and Myrddyn Phillips |
The name the hill is listed by is Clipiau Duon and it is adjoined to the Esgeiriau Gwynion group of hills, which are situated in the southern part of North Wales (Region A, Sub-Region A3), and it is positioned with the A494 road to its north-west and a minor road to its east, and has the village of Llanymawddwy towards the south.
When the initial P10 sub list was completed in June 2020 this hill was listed with an estimated c 9m of drop, based on an estimated c 585m summit height and an estimated c 576m bwlch height, with both heights based on interpolation of 5m contouring that appeared on online mapping.
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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 586.3m summit height and a 576.1m 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: Esgeiriau Gwynion
Name: Clipiau Duon
OS 1:50,000 map: 125
Summit Height: 586.3m (LIDAR)
Summit Grid Reference: SH 90074 22779 (LIDAR)
Bwlch Height: 576.1m (LIDAR)
Bwlch Grid Reference: SH 89864 22477 (LIDAR)
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:
Welsh Highland P15s
Welsh Highland Subs
Aled Williams and Myrddyn Phillips (January 2024)
Mapping Mountains - Hill Reclassifications - Welsh Highlands - Uchafion Cymru
Cefn Tyle Brych (SN 903 014) – Welsh Highland Sub deletion (111th 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 Cefn Tyle Brych (SN 903 014) |
The criteria for the list that this deletion applies to are:
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Welsh Highlands - Uchafion Cymru by Aled Williams and Myrddyn Phillips |
The name the hill is listed by is Cefn Tyle Brych and it is adjoined to the Craig y Llyn group of hills, which are situated in the southern part of South Wales (Region B, Sub-Region B5), and it is positioned with the A465 road to its north and the A4061 road to its east, and has the village of Treherbert towards the south-east.
When the initial P10 sub list was completed in June 2020 this hill was listed with an estimated c 11m of drop, based on a 539m summit height and an estimated c 528m bwlch height, based on interpolation of 5m contouring that appeared on online mapping.
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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 deletion of this hill from Welsh Highland Sub status is due to LIDAR analysis, resulting in a 538.5m summit height and a 528.7m 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: Craig y Llyn
Name: Cefn Tyle Brych
OS 1:50,000 map: 170
Summit Height: 538.5m (LIDAR)
Summit Grid Reference: SN 90321 01411 (LIDAR)
Bwlch Height: 528.7m (LIDAR)
Bwlch Grid Reference: SN 90482 01905 (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:
Welsh Highland P15s
Welsh Highland Subs
Aled Williams and Myrddyn Phillips (January 2024)
Mapping Mountains - Hill Reclassifications - Welsh Highlands - Uchafion Cymru
Pt. 557.6m (SO 023 822) – Welsh Highland Sub deletion (110th 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 Pt. 557.6m (SO 023 822) |
The criteria for the list that this deletion applies to are:
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Welsh Highlands - Uchafion Cymru by Aled Williams and Myrddyn Phillips |
The hill is being listed by the point (Pt. 557.6m) notation, and it is adjoined to the Hirddywel group of hills, which are situated in the northern part of South Wales (Region B, Sub-Region B2), and it is positioned with minor roads to its north-west, south-west and north-east, and the B4518 and A470 roads to its west and the A483 road to its east, and has the town of Llanidloes towards the west north-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 with an estimated c 11m of drop, based on the 558m summit spot height that appears on the contemporary Ordnance Survey 1:25,000 Explorer map and an estimated c 547m bwlch height, based on the 1796ft (547.4m) height that appears on the Ordnance Survey series of Six-Inch maps.
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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 557.6m summit height and a 547.8m 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: Hirddywel
Name: Pt. 557.6m
OS 1:50,000 map: 136
Summit Height: 557.6m (LIDAR)
Summit Grid Reference: SO 02324 82248 (LIDAR)
Bwlch Height: 547.8m (LIDAR)
Bwlch Grid Reference: SO 02100 81851 (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:
Welsh Highland P15s
Welsh Highland Subs
Aled Williams and Myrddyn Phillips (January 2024)
Mapping Mountains - Hill Reclassifications - Welsh Highlands - Uchafion Cymru
Esgair Dafydd (SN 836 453) – Welsh Highland Sub deletion (109th 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 Esgair Dafydd (SN 836 453) |
The criteria for the list that this deletion applies to are:
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Welsh Highlands - Uchafion Cymru by Aled Williams and Myrddyn Phillips |
The name the hill is listed by is Esgair Dafydd and it is adjoined to the Drygarn Fawr group of hills, which are situated in the northern part of South Wales (Region B, Sub-Region B1), and it is positioned with the A483 road to its south-east, and has the town of Llanwrtyd towards the east north-east.
When the initial P10 sub list was completed in June 2020 this hill was listed with an estimated c 11m of drop, based on the 505m summit spot height that appears on the contemporary Ordnance Survey 1:25,000 Explorer map and an estimated c 494m bwlch height, based on interpolation of 5m contouring that appeared on online mapping.
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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 deletion of this hill from Welsh Highland Sub status is due to LIDAR analysis, resulting in a 504.5m summit height and a 494.9m bwlch height, with these values giving this hill 9.5m of drop, which is insufficient for it to be classified as a Welsh Highland Sub.
The full details for the hill are:
Group: Drygarn Fawr
Name: Esgair Dafydd
OS 1:50,000 map: 147
Summit Height: 504.5m (LIDAR)
Summit Grid Reference: SN 83641 45366 (LIDAR)
Bwlch Height: 494.9m (LIDAR)
Bwlch Grid Reference: SN 83970 45692 (LIDAR)
Drop: 9.5m (LIDAR)
For the additions, deletions and reclassifications to the Welsh Highlands – Uchafion Cymru reported on Mapping Mountains please consult the following Change Registers:
Welsh Highland P15s
Welsh Highland Subs
Aled Williams and Myrddyn Phillips (January 2024)
Mapping Mountains - Hill Reclassifications - Welsh Highlands - Uchafion Cymru
Pt. 509.8m (SN 827 479) – Welsh Highland Sub addition (108th 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 Pt. 509.8m (SN 827 479) |
The criteria for the list that this addition applies to are:
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Welsh Highlands - Uchafion Cymru by Aled Williams and Myrddyn Phillips |
The hill is being listed by the point (Pt. 509.8m) notation, and it is adjoined to the Drygarn Fawr group of hills, which are situated in the northern part of South Wales (Region B, Sub-Region B1), and it is positioned with a minor road to its north-west and east, and the A483 road to its south-east, and has the town of Llanwrtyd towards the east south-east.
When the initial P10 sub list was completed in June 2020 this hill was not listed as contour configuration did not give it sufficient interpolated drop for it to be included, with the contemporary Ordnance Survey 1:25,000 Explorer map having an uppermost 500m ring contour that also connects with its critical bwlch.
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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 509.8m summit height and a 499.5m 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: Drygarn Fawr
Name: Pt. 509.8m
OS 1:50,000 map: 147
Summit Height: 509.8m (LIDAR)
Summit Grid Reference: SN 82700 47937 (LIDAR)
Bwlch Height: 499.5m (LIDAR)
Bwlch Grid Reference: SN 82706 47648 (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:
Welsh Highland P15s
Welsh Highland Subs
Aled Williams and Myrddyn Phillips (January 2024)
Mapping Mountains - Hill Reclassifications - Welsh Highlands - Uchafion Cymru
Carreg Wen Fawr (SN 820 624) – Welsh Highland Sub deletion (107th 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 Carreg Wen Fawr (SN 820 624) |
The criteria for the list that this deletion applies to are:
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Welsh Highlands - Uchafion Cymru by Aled Williams and Myrddyn Phillips |
The name the hill is listed by is Carreg Wen Fawr and it is adjoined to the Drygarn Fawr group of hills, which are situated in the northern part of South Wales (Region B, Sub-Region B1), and it is positioned with a minor road to its east and south, and has the village of Pontrhydfendigaid towards the west north-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 with an estimated c 10m of drop, based on the 527m summit spot height that appears on the contemporary Ordnance Survey 1:25,000 Explorer map and an estimated c 517m bwlch height, based on interpolation of 5m contouring that appeared on online mapping, with an accompanying note stating:
Summit-area height of 1726ft (526.1m) on OS 6" Map (1888) is in a different position to the 527m height given on paper and enlarged-scale online OS maps.
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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 526.0m summit height and a 516.6m bwlch height, with these values giving this hill 9.4m of drop, which is insufficient for it to be classified as a Welsh Highland Sub.
The full details for the hill are:
Group: Drygarn Fawr
Name: Carreg Wen Fawr
OS 1:50,000 map: 147
Summit Height: 526.0m (LIDAR)
Summit Grid Reference: SN 82080 62445 (LIDAR)
Bwlch Height: 516.6m (LIDAR)
Bwlch Grid Reference: SN 82049 62279 (LIDAR)
Drop: 9.4m (LIDAR)
For the additions, deletions and reclassifications to the Welsh Highlands – Uchafion Cymru reported on Mapping Mountains please consult the following Change Registers:
Welsh Highland P15s
Welsh Highland Subs
Aled Williams and Myrddyn Phillips (January 2024)
Mapping Mountains - Hill Reclassifications - Welsh Highlands - Uchafion Cymru
Graig Fawr (SN 776 685) – Welsh Highland Sub addition (106th 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 Graig Fawr (SN 776 685) |
The criteria for the list that this addition applies to are:
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Welsh Highlands - Uchafion Cymru by Aled Williams and Myrddyn Phillips |
The name the hill is listed by is Graig Fawr and it is adjoined to the Carn yr Hyrddod group of hills, which are situated in the northern part of South Wales (Region B, Sub-Region B1), and it is positioned with the B4343 road to its west and a minor road to its south, and has the village of Pont-rhyd-y-groes towards the north-west.
When the initial P10 sub list was completed in June 2020 this hill was listed with an estimated c 8m of drop, based on a 502m summit height and an estimated c 494m bwlch height, based on interpolation of 5m contouring that appeared on online mapping.
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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 502.4m summit height and a 492.0m 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: Carn yr Hyrddod
Name: Graig Fawr
OS 1:50,000 map: 135, 147
Summit Height: 502.4m (LIDAR)
Summit Grid Reference: SN 77653 68592 (LIDAR)
Bwlch Height: 492.0m (LIDAR)
Bwlch Grid Reference: SN 77643 68675 (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:
Welsh Highland P15s
Welsh Highland Subs
Aled Williams and Myrddyn Phillips (January 2024)
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