Y Trichant
– Hill Reclassifications
Y
Trichant are the Welsh hills at or above 300m and below 40om in
height that have a minimum drop of 30m, with these hills forming the 300m
height band within the listing of the Twmpau
(thirty welsh metre prominences and upward). Accompanying the main P30 list is a sub list
entitled the 300m Sub-Trichant with the
qualification to this sub category being all Welsh hills at or above 300m and
below 400m in height with 20m or more and below 30m of drop. The Introduction to this list giving its
publication history appeared on Mapping Mountains on 13.05.17.
The list is authored by Myrddyn
Phillips and the posts that have appeared on Mapping Mountains detailing the
additions, reclassifications and deletions to the main P30 list and the sub
list appear below presented chronologically in receding order.
Mapping Mountains - Hill Reclassifications - Y Trichant
Mynydd Deulyn (SH 756 609) – Sub-Trichant addition (35th reclassification)
Mynydd Deulyn (SH 756 609) – Sub-Trichant addition (35th reclassification)
There has been an addition to the list of Y Trichant – The 300m Hills of Wales, with the summit height, bwlch height and their locations, the drop and status of the hill confirmed via map spot height and contour interpolation.
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| Mynydd Deulyn (SH 756 609) and its higher northerly summit |
The criteria for the list that this addition applies to are:
Y Trichant – The 300m Hills of Wales – Welsh hills at or above 300m and below 400m in height that have 30m minimum drop, with an accompanying sub list entitled the Sub-Trichant with the criteria for this sub category being all Welsh hills at or above 300m and below 400m in height with 20m or more and below 30m of drop. The list is authored by Myrddyn Phillips, with the Introduction to the list and the renaming of it appearing on Mapping Mountains on the 13th May 2017.
The name the hill is listed by is Mynydd Deulyn and it is adjoined to the Carneddau group of hills, which are situated in the north-western part of North Wales (Region A, Sub-Region A1), and it is positioned between Llyn Crafnant to its west and Llyn Geirionydd to its east, with the A5 road to its south and the B5106 road, the Afon Conwy and the A470 road to its east, and has the village of Capel Curig towards the south-west and the town of Llanrwst towards the east.
When the original 300m height band of Welsh P30 hills were published on Geoff Crowder’s v-g.me website this hill was not included in the Hills to be surveyed sub list that accompanied the main P30 list, as it did not meet the criteria then used for this sub category.
 |
| Extract from the Ordnance Survey 1:25,000 Explorer map |
When the sub list was standardised, and interpolated heights and drop values also included the details for this hill were re-evaluated. Its details were also 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.
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 the online Vector Map Local. These re-assessments resulted in the hill being listed with an estimated c 20m of drop.
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| Extract from the OS Maps website |
Therefore, the addition of this hill to Sub-Trichant status is due to the summit spot height and interpolation of bwlch contouring resulting in a 382m summit height based on the spot height that appears on the Ordnance Survey 1:25,000 Explorer map and an estimated bwlch height of c 362m based on interpolation of bwlch contouring between 360m – 365m on the OS Maps website, with these values giving this hill c 20m of drop, which is sufficient for it to be classified as a Sub-Trichant.
The full details for the hill are:
Group: Carneddau
Name: Mynydd Deulyn
OS 1:50,000 map: 115
Summit Height: 382m (spot height)
Summit Grid Reference: SH 75657 60903 (spot height)
Bwlch Height: c 362m (interpolation)
Bwlch Grid Reference: SH 75760 61053 (interpolation)
Drop: c 20m
Myrddyn Phillips (November 2019)
Pt. 343.1m (SH 728 584) – Sub-Trichant addition (34th reclassification)
There has been confirmation of an addition to the list of Y Trichant – The 300m Hills of Wales, with the summit height, bwlch height and their locations, the drop and status of the hill confirmed by LIDAR analysis conducted by Myrddyn Phillips.
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| LIDAR image of Pt. 343.1m (SH 728 584) |
The criteria for the list that this addition applies to are:
Y Trichant – The 300m Hills of Wales – Welsh hills at or above 300m and below 400m in height that have 30m minimum drop, with an accompanying sub list entitled the Sub-Trichant with the criteria for this sub category being all Welsh hills at or above 300m and below 400m in height with 20m or more and below 30m of drop. The list is authored by Myrddyn Phillips, with the Introduction to the list and the renaming of it appearing on Mapping Mountains on the 13th May 2017.
The hill is being listed by the point (Pt. 343.1m) notation as an appropriate name for it either through local enquiry and / or historic research has not been found by the author, and it is adjoined to the Carneddau 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 village of Capel Curig towards the south-west.
When the original 300m height band of Welsh P30 hills were published on Geoff Crowder’s v-g.me website this hill was not included in the Hills to be surveyed sub list that accompanied the main P30 list, as it did not meet the criteria then used for this sub category.
When the sub list was standardised, and interpolated heights and drop values also included the details for this hill were re-evaluated. Its details were also 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 available on any other publicly available Ordnance Survey map. The hill was subsequently listed with an estimated c 19m of drop, based on the 344m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and an estimated bwlch height of c 325m based on bwlch contouring between 320m – 330m.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
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 the online Vector Map Local. This latest re-assessment resulted in the hill being listed with an estimated c 21m of drop, based on the 344m summit spot height and an estimated bwlch height of c 323m based on bwlch contouring between 320m – 325m.
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| Extract from 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.
The confirmation of the addition of Pt. 343.1m to Sub-Trichant status is due to LIDAR analysis, resulting in a 343.1m summit height and a 322.6m bwlch height, with these values giving this hill 20.5m of drop which is sufficient for it to be classified as a Sub-Trichant.
The full details for the hill are:
Group: Carneddau
Name: Pt. 343.1m
OS 1:50,000 map: 115
Summit Height: 343.1m (LIDAR)
Summit Grid Reference: SH 72842 58446 (LIDAR)
Bwlch Height: 322.6m (LIDAR)
Bwlch Grid Reference: SH 72831 58352 (LIDAR)
Drop: 20.5m (LIDAR)
Myrddyn Phillips (November 2019)
Clogwyn Mawr (SH 728 583) – Sub-Trichant addition (33rd reclassification)
There has been confirmation of an addition to the list of Y Trichant – The 300m Hills of Wales, with the summit height, bwlch height and their locations, the drop and status of the hill confirmed by LIDAR analysis conducted by Myrddyn Phillips.
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| LIDAR image of Clogwyn Mawr (SH 728 583) |
The criteria for the list that this addition applies to are:
Y Trichant – The 300m Hills of Wales – Welsh hills at or above 300m and below 400m in height that have 30m minimum drop, with an accompanying sub list entitled the Sub-Trichant with the criteria for this sub category being all Welsh hills at or above 300m and below 400m in height with 20m or more and below 30m of drop. The list is authored by Myrddyn Phillips, with the Introduction to the list and the renaming of it appearing on Mapping Mountains on the 13th May 2017.
The name the hill is listed by is Clogwyn Mawr and it is adjoined to the Carneddau 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 village of Capel Curig towards the south-west.
When the original 300m height band of Welsh P30 hills were published on Geoff Crowder’s v-g.me website this hill was not included in the Hills to be surveyed sub list that accompanied the main P30 list, as it did not meet the criteria then used for this sub category.
When the sub list was standardised, and interpolated heights and drop values also included the details for this hill were re-evaluated. Its details were also 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 available on any other publicly available Ordnance Survey map. The hill was subsequently listed with an estimated c 23m of drop, based on the 347m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and an estimated bwlch height of c 324m based on bwlch contouring between 320m – 330m.
 |
| Extract from the Ordnance Survey 1:25,000 Explorer map |
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 the online Vector Map Local. This latest re-assessment resulted in the hill being listed with an estimated c 24m of drop, based on the 347m summit spot height and an estimated bwlch height of c 323m based on bwlch contouring between 320m – 325m.
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| Extract from 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.
The confirmation of the addition of Clogwyn Mawr to Sub-Trichant status is due to LIDAR analysis, resulting in a 345.7m summit height and a 321.8m bwlch height, with these values giving this hill 23.9m of drop which is sufficient for it to be classified as a Sub-Trichant.
The full details for the hill are:
Group: Carneddau
Name: Clogwyn Mawr
OS 1:50,000 map: 115
Summit Height: 345.7m (LIDAR)
Summit Grid Reference: SH 72874 58313 (LIDAR)
Bwlch Height: 321.8m (LIDAR)
Bwlch Grid Reference: SH 72844 58514 (LIDAR)
Drop: 23.9m (LIDAR)
Myrddyn Phillips (November 2019)
Dinas (SH 699 738) – Sub-Trichant addition (32nd reclassification)
Significant Height Revisions post for Dinas
There has been confirmation of an addition to the list of Y Trichant – The 300m Hills of Wales, with the summit height, bwlch height and their locations, the drop and status of the hill confirmed by LIDAR analysis conducted by Myrddyn Phillips.
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| LIDAR summit image of Dinas (SH 699 738) |
The criteria for the list that this addition applies to are:
Y Trichant – The 300m Hills of Wales – Welsh hills at or above 300m and below 400m in height that have 30m minimum drop, with an accompanying sub list entitled the Sub-Trichant with the criteria for this sub category being all Welsh hills at or above 300m and below 400m in height with 20m or more and below 30m of drop. The list is authored by Myrddyn Phillips, with the Introduction to the list and the renaming of it appearing on Mapping Mountains on the 13th May 2017.
The name the hill is listed by is Dinas and it is adjoined to the Carneddau 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 A55 road to its north-west, and has the town of Penmaen-mawr towards the north-east and the town of Llanfairfechan towards the north-west.
When the original 300m height band of Welsh P30 hills were published on Geoff Crowder’s v-g.me website this hill was not included in the Hills to be surveyed sub list that accompanied the main P30 list, as it did not meet the criteria then used for this sub category.
After the sub list was standardised, and interpolated heights and drop values also included the details for this hill were re-evaluated, but as the contemporary Ordnance Survey 1:25,000 Explorer map did not have a summit spot height and only an uppermost 320m continuous contour and bwlch contouring between 300m – 310m, an accurate interpolated drop value was hard to determine.
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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 available on any other publicly available Ordnance Survey map.
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 the online Vector Map Local. These re-assessments resulted in the hill being listed with an estimated c 24m of drop, based on an estimated summit height of c 328m and an estimated bwlch height of c 304m.
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| Extract from 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.
 |
| LIDAR bwlch image for Dinas |
The confirmation of the addition of Dinas to Sub-Trichant status is due to LIDAR analysis, resulting in a 325.9m summit height and a 301.5m bwlch height, with these values giving this hill 24.4m of drop which is sufficient for it to be classified as a Sub-Trichant.
The full details for the hill are:
Group: Carneddau
Name: Dinas
OS 1:50,000 map: 115
Summit Height: 325.9m (LIDAR)
Summit Grid Reference: SH 69978 73828 (LIDAR)
Bwlch Height: 301.5m (LIDAR)
Bwlch Grid Reference: SH 70198 73941 (LIDAR)
Drop: 24.4m (LIDAR)
Myrddyn Phillips (November 2019)
Caer Eini (SJ 000 412) – Sub-Trichant reclassified to Trichant (31st reclassification)
Survey post for Caer Eini
There has been confirmation of a reclassification to a hill listed in the Y Trichant, with the summit height, bwlch height and their locations, the drop and status of the hill confirmed by a Trimble GeoXH 6000 survey and LIDAR analysis conducted by Myrddyn Phillips, with the former taking place on the 25th October 2014.
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| Caer Eini (SJ 000 412) |
The criteria for the list that this reclassification applies to are:
Y Trichant – Welsh hills at or above 300m and below 400m in height that have 30m minimum drop, with an accompanying sub list entitled the Sub-Trichant with the criteria for this sub category being all Welsh hills at or above 300m and below 400m in height with 20m or more and below 30m of drop. The list is authored by Myrddyn Phillips, with the Introduction to the list and the renaming of it appearing on Mapping Mountains on the 13th May 2017.
The name of the hill is Caer Eini 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 A494 road to its south-east, and has the town of Y Bala towards the south-west.
When the original 300m height band of Welsh P30 hills were published on Geoff Crowder’s v-g.me website this hill was included in the Hills to be surveyed sub list that accompanied the main P30 list, as it did not meet the criteria then used for the main P30 list.
After the sub list was standardised, and interpolated heights and drop values also included the details for this hill were re-evaluated and it was listed with 31m of drop, based on the 365m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and the 334m bwlch spot height that appears on the Ordnance Survey Vector Map Local hosted on the Geograph website and which is entitled the Interactive Coverage Map.
 |
| Extract from the Ordnance Survey Vector Map Local hosted on the Geograph website |
However, it was not until the survey with the Trimble GeoXH 6000 and when LIDAR became available that the details for this hill could be accurately re-assessed. The LIDAR (Light Detection & Ranging) technique produced highly accurate height data that is now freely available for much of England and Wales.
 |
| LIDAR bwlch image of Caer Eini |
The confirmation of the reclassification of Caer Eini to Trichant status is due to a survey with the Trimble GeoXH 6000 and LIDAR analysis, resulting in a 365.7m summit height and a 334.4m bwlch height, with these values giving this hill 31.3m of drop which is sufficient for it to be classified as a Trichant.
The full details for the hill are:
Group: Arenig
Name: Caer Eini
OS 1:50,000 map: 125
Summit Height: 365.7m (converted to OSGM15)
Summit Grid Reference: SJ 00048 41275
Bwlch Height: 334.4m (LIDAR)
Bwlch Grid Reference: SH 99599 41003 (LIDAR)
Drop: 31.3m (Trimble summit and LIDAR bwlch)
Mapping Mountains - Hill Reclassifications - Y Trichant
Pt. 368.9m (SH 991 412) – Sub-Trichant addition (30th reclassification)
There has been confirmation of an addition of a hill to the list of the Y Trichant, with the summit height, bwlch height and their locations, the drop and status of the hill confirmed by LIDAR analysis, and a Trimble GeoXH 6000 summit survey conducted by Myrddyn Phillips, with the latter taking place on the 25th October 2014.
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| Pt. 368.9m (SH 991 412) |
The criteria for the list that this addition applies to are:
Y Trichant – Welsh hills at or above 300m and below 400m in height that have 30m minimum drop, with an accompanying sub list entitled the Sub-Trichant with the criteria for this sub category being all Welsh hills at or above 300m and below 400m in height with 20m or more and below 30m of drop. The list is authored by Myrddyn Phillips, with the Introduction to the list and the renaming of it appearing on Mapping Mountains on the 13th May 2017.
As I do not know an appropriate name for the hill either from historic documentation or local enquiry it is being listed under the point (Pt. 368.9m) notation, 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 A494 road to its south-east, and has the town of Y Bala towards the south-west.
When the original 300m height band of Welsh P30 hills were published on Geoff Crowder’s v-g.me website this hill was not included in the Hills to be surveyed sub list that accompanied the main P30 list, as it did not meet the criteria then used for this sub category.
After the sub list was standardised, and interpolated heights and drop values also included the details for this hill were re-evaluated and it was listed with 25m of drop, based on the 369m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and the 344m bwlch spot height that appears on the Ordnance Survey Vector Map Local hosted on the Geograph website and which is entitled the Interactive Coverage Map.
 |
| Extract from the Ordnance Survey Vector Map Local hosted on the Geograph website |
However, it was not until LIDAR became available that the details for this hill could be accurately re-assessed. The LIDAR (Light Detection & Ranging) technique produced highly accurate height data that is now freely available for much of England and Wales.
 |
| LIDAR image of Pt. 368.9m (SH 991 412) |
The confirmation of the addition of Pt. 368.9m to Sub-Trichant status is due to LIDAR analysis, resulting in a 368.9m summit height and a 344.2m bwlch height, with these values giving this hill 24.7m of drop which is sufficient for it to be classified as a Sub-Trichant.
The full details for the hill are:
Group: Arenig
Name: Pt. 368.9m
OS 1:50,000 map: 125
Summit Height: 368.9m (LIDAR)
Summit Grid Reference: SH 99136 41259 (LIDAR)
Bwlch Height: 344.2m (LIDAR)
Bwlch Grid Reference: SH 99216 41144 (LIDAR)
Drop: 24.7m (LIDAR)
Myrddyn Phillips (November 2019)
Bryn Hafod y Llan (SH 945 531) – Sub-Trichant addition (29th reclassification)
There has been an addition of a hill to the list of the Y Trichant, with the summit height, bwlch height and their locations, the drop and status of the hill confirmed by LIDAR analysis initially conducted by Aled Williams and subsequently by Myrddyn Phillips.
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| LIDAR image of Bryn Hafod y Llan (SH 945 531) |
The criteria for the list that this addition applies to are:
Y Trichant – Welsh hills at or above 300m and below 400m in height that have 30m minimum drop, with an accompanying sub list entitled the Sub-Trichant with the criteria for this sub category being all Welsh hills at or above 300m and below 400m in height with 20m or more and below 30m of drop. The list is authored by Myrddyn Phillips, with the Introduction to the list and the renaming of it appearing on Mapping Mountains on the 13th May 2017.
The name of the hill is Bryn Hafod y Llan, and it is adjoined to the Mynydd Hiraethog group of hills, which are situated in the north-eastern part of North Wales (Region A, Sub-Region A2), and it is positioned with the A5 road to its south and the B4501 road to its east, and has the Alwen Reservoir to the north-east and the village of Cerrigydrudion towards the south.
When the original 300m height band of Welsh P30 hills were published on Geoff Crowder’s v-g.me website this hill was not included in the Hills to be surveyed sub list that accompanied the main P30 list, as it did not meet the criteria then used for this sub category.
 |
| Extract from the Ordnance Survey 1:25,000 Explorer map |
After the sub list was standardised, and interpolated heights and drop values also included the details for this hill were re-evaluated and it was listed with an estimated c 18m of drop, based on an estimated summit height of c 397m and a bwlch height of 379m that appears 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 Vector Map Local hosted on the Geograph 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.
The addition of Bryn Hafod y Llan to Sub-Trichant status is due to LIDAR analysis, resulting in a 398.7m summit height and a 378.5m bwlch height, with these values giving this hill 20.1m of drop which is sufficient for it to be classified as a Sub-Trichant.
The full details for the hill are:
Group: Mynydd Hiraethog
Name: Bryn Hafod y Llan
OS 1:50,000 map: 116
Summit Height: 398.7m (LIDAR)
Summit Grid Reference: SH 94590 53115 (LIDAR)
Bwlch Height: 378.5m (LIDAR)
Bwlch Grid Reference: SH 94564 52682 (LIDAR)
Drop: 20.1m (LIDAR)
Myrddyn Phillips (September 2019)
Cerrig y Ddinas (SH 754 739) – Sub-Trichant reclassified to Trichant (28th reclassification)
Survey post for Cerrig y Ddinas
There has been a reclassification to a hill that is listed in the Y Trichant, with the summit height and its position initially ascertained from LIDAR analysis and the summit height, bwlch height and their locations, the drop and status of the hill subsequently confirmed by a survey with the Trimble GeoXH 6000 conducted by Myrddyn Phillips, with the latter taking place on the 22nd May 2019.
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| Cerrig y Ddinas (SH 754 739) |
The criteria for the list that this reclassification applies to are:
Y Trichant – Welsh hills at or above 300m and below 400m in height that have 30m minimum drop, with an accompanying sub list entitled the Sub-Trichant with the criteria for this sub category being all Welsh hills at or above 300m and below 400m in height with 20m or more and below 30m of drop. The list is authored by Myrddyn Phillips, with the Introduction to the list and the renaming of it appearing on Mapping Mountains on the 13th May 2017.
The name of the hill is Cerrig y Ddinas and it is adjoined to the Carneddau 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 A55 road and the coast to its north, and has the town of Conwy towards the north-east.
When the original 300m height band of Welsh P30 hills were published on Geoff Crowder’s v-g.me website this hill was included in the Hills to be surveyed sub list as it did not meet the criteria then used for the main P30 list; however the main P30 and accompanying sub list has now been standardised and interpolated heights and drop values also included.
When this list was standardised and interpolated heights also included this hill was listed with an estimated c 26m of drop, based on the 312m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map which was prioritised in favour of the 314m summit spot height that appears on the Ordnance Survey 1:50,000 Landranger map, and an estimated bwlch height of c 286m based on interpolation of 10m contouring on the contemporary Ordnance Survey 1:25,000 Explorer map.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
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| Extract from the Ordnance Survey 1:50,000 Landranger map |
The details for this hill were re-examined when the OS Maps website became available online. This is the replacement for OS Get-a-map and has contours at 5m intervals. The mapping on OS Maps shows this hill with bwlch contouring between 280m – 285m with an estimated height of c 284m giving this hill a drop value nearer 30m.
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| Extract from 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, however LIDAR coverage only takes in the summit of this hill.
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| LIDAR summit image of Cerrig y Ddinas |
The reclassification of this hill to Trichant status is due to a Trimble GeoXH 6000 bwlch and summit survey, resulting in a 313.5m summit height and a 283.0m bwlch height, with these values giving this hill 30.5m of drop, which is sufficient for this hill to be classified as a Trichant.
The full details for the hill are:
Group: Carneddau
Name: Cerrig y Ddinas
OS 1:50,000 map: 115
Summit Height: 313.5m (converted to OSGM15)
Summit Grid Reference: SH 75427 73948
Bwlch Height: 283.0m (converted to OSGM15)
Bwlch Grid Reference: SH 75140 73786
Drop: 30.5m (converted to OSGM15)
Maen Esgob (SH 748 759) – Sub-Trichant reclassified to Trichant (27th reclassification)
Survey post for Maen Esgob
There has been a reclassification to a hill included in the listing of the Y Trichant, with the summit height, bwlch height and their locations, the drop and status of the hill initially confirmed by LIDAR analysis and subsequently by a survey with the Trimble GeoXH 6000 conducted by Myrddyn Phillips, with the latter taking place on the 22nd May 2019.
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| Maen Esgob (SH 748 759) |
The criteria for the list that this reclassification applies to are:
Y Trichant – Welsh hills at or above 300m and below 400m in height that have 30m minimum drop, with an accompanying sub list entitled the Sub-Trichant with the criteria for this sub category being all Welsh hills at or above 300m and below 400m in height with 20m or more and below 30m of drop. The list is authored by Myrddyn Phillips, with the Introduction to the list and the renaming of it appearing on Mapping Mountains on the 13th May 2017.
The name of the hill is Maen Esgob and it is adjoined to the Carneddau 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 A55 road and the coast to its north, and has the town of Conwy towards the north-east.
When the original 300m height band of Welsh P30 hills were published on Geoff Crowder’s v-g.me website this hill was included in the Hills to be surveyed sub list as it did not meet the criteria then used for the main P30 list; however the main P30 and accompanying sub list has now been standardised and interpolated heights and drop values also included.
When this list was standardised and interpolated heights also included this hill was listed with an estimated c 27m of drop, based on an estimated c 302m summit height and an estimated c 275m bwlch height, with each based on interpolation of 10m contouring on the contemporary 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-examined when the OS Maps website became available online. This is the replacement for OS Get-a-map and has contours at 5m intervals. The mapping on OS Maps shows this hill as having seven continuous 5m contour rings, implying that the hill has at least 30m of drop.
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 Maen Esgob |
The reclassification of this hill to Trichant status is due to LIDAR analysis, coupled with a subsequent Trimble GeoXH 6000 bwlch and summit survey, resulting in 30.6m of drop produced via LIDAR and a 300.0m summit height and a 269.2m bwlch height, with these values giving this hill 30.8m of drop produced via the Trimble GeoXH 6000 survey, with these values being sufficient for this hill to be classified as a Trichant.
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| The Trimble GeoXH 6000 gathering data at the summit of Maen Esgob |
The full details for the hill are:
Group: Carneddau
Name: Maen Esgob
OS 1:50,000 map: 115
Summit Height: 300.0m (converted to OSGM15)
Summit Grid Reference: SH 74877 75900
Bwlch Height: 269.2m (converted to OSGM15)
Bwlch Grid Reference: SH 74870 75664
Drop: 30.8m (converted to OSGM15)
Pen Rhiw Warren (ST 214 904) – Trichant addition (26th reclassification)
Significant Height Revisions post for Pen Rhiw Warren
There has been an addition to the list of the Y Trichant, with the summit height, bwlch height and their locations, the drop and status of the hill confirmed by LIDAR analysis conducted by Myrddyn Phillips.
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| LIDAR image of Pen Rhiw Warren (ST 214 904) |
The criteria for the list that this addition applies to are:
Y Trichant – Welsh hills at or above 300m and below 400m in height that have 30m minimum drop, with an accompanying sub list entitled the Sub-Trichant with the criteria for this sub category being all Welsh hills at or above 300m and below 400m in height with 20m or more and below 30m of drop. The list is authored by Myrddyn Phillips, with the Introduction to the list and the renaming of it appearing on Mapping Mountains on the 13th May 2017.
The name of the hill is Pen Rhiw Warren and its present state is the result of mine spoil, 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 A468 road and the Afon Rhymni (Rhymney River) to its south, the B4251 and A467 roads and the Afon Sirhywi (Sirhowy River) towards the north, and has the town of Caerffili (Caerphilly) towards the west south-west.
This hill was not included in the main P30 list or the accompanying Hills to be surveyed sub list when the original Welsh 300m P30 hills were published on Geoff Crowder’s v-g.me website, as it was considered not to meet the criteria then used for this list. This list has now been standardised and interpolated heights and drop values also included in the main P30 and the accompanying sub 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 OS Maps website became available online. This is the replacement for OS Get-a-map and has contours at 5m intervals and for the majority of land comprising old mine and quarry workings, and rail and road cuttings it shows present day continuous contours, as opposed to the broken contours on contemporary Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer maps. The mapping on OS Maps shows this hill as having eight continuous 5m contour rings, implying that the hill has at least 35m of drop.
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| Extract from 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.
The addition of this hill to Y Trichant status is due to LIDAR analysis, resulting in a 350.5m summit height and a 313.9m bwlch height, with these values giving this hill 36.6m of drop which is sufficient for it to be classified as a Trichant.
The inclusion of this hill to Trichant status is dependent upon using the present-day height of the hill, which has been terra-formed by man’s intrusion and is the result of raised mine spoil. As the hill in its present form is considered solid and stable its inclusion as a Trichant is accepted as a present-day representation of the land.
The full details for the hill are:
Group: Cymoedd Gwent
Name: Pen Rhiw Warren
OS 1:50,000 map: 171
Summit Height: 350.5m (LIDAR)
Summit Grid Reference: ST 21463 90441 (LIDAR)
Bwlch Height: 313.9m (LIDAR)
Bwlch Grid Reference: ST 21869 90427 (LIDAR)
Drop: 36.6m (LIDAR)
Myrddyn Phillips (August 2019)
Llanbradach Tip (ST 138 913) – Sub-Trichant addition (25th reclassification)
There has been an addition of a hill to the Y Trichant list, with the summit height, bwlch height and their locations, the drop and status of the hill confirmed by LIDAR analysis conducted by Myrddyn Phillips.
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| LIDAR image of Llanbradach Tip (ST 138 913) |
The criteria for the list that this addition applies to are:
Y Trichant – Welsh hills at or above 300m and below 400m in height that have 30m minimum drop, with an accompanying sub list entitled the Sub-Trichant with the criteria for this sub category being all Welsh hills at or above 300m and below 400m in height with 20m or more and below 30m of drop. The list is authored by Myrddyn Phillips, with the Introduction to the list and the renaming of it appearing on Mapping Mountains on the 13th May 2017.
The name this hill is listed by is Llanbradach Tip and as its name implies the hill is the result of mine spoil and it is the western of three pyramidal tips, 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 B4263 road to its south-west and the A469 road and the Afon Rhymni (Rhymney River) to its east, and has the small community of Llanbradach towards its south-east.
When the original 300m height band of Welsh P30 hills were published on Geoff Crowder’s v-g.me website this hill was not included in the Hills to be surveyed sub list as it was thought not to meet the criteria then used; however this sub list has now been standardised and interpolated heights and drop values also included in the main P30 and the accompanying sub list.
When this list was standardised and interpolated heights also included the area surrounding this hill was re-assessed but as the Ordnance Survey 1:25,000 Explorer map shows the hill to have no contours and the 1:50,000 Landranger map shows the hill with two ring contours its drop value was difficult to estimate.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
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| Extract from the Ordnance Survey 1:50,000 Landranger 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 addition of this hill to Sub-Trichant status is due to LIDAR analysis, resulting in a 331.3m summit height and a 310.4m bwlch height, with these values giving this hill 20.9m of drop which is sufficient for it to be classified as a Sub-Trichant.
The full details for the hill are:
Group: Cymoedd Gwent
Name: Llanbradach Tip
OS 1:50,000 map: 171
Summit Height: 331.3m (LIDAR)
Summit Grid Reference: ST 13843 91345 (LIDAR)
Bwlch Height: 310.4m (LIDAR)
Bwlch Grid Reference: ST 13784 91419 (LIDAR)
Drop: 20.9m (LIDAR)
Myrddyn Phillips (July 2019)
Llanbradach Tip (ST 139 913) – Sub-Trichant addition (24th reclassification)
There has been an addition of a hill to the Y Trichant list, with the summit height, bwlch height and their locations, the drop and status of the hill confirmed by LIDAR analysis conducted by Myrddyn Phillips.
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| LIDAR image of Llanbradach Tip (ST 139 913) |
The criteria for the list that this addition applies to are:
Y Trichant – Welsh hills at or above 300m and below 400m in height that have 30m minimum drop, with an accompanying sub list entitled the Sub-Trichant with the criteria for this sub category being all Welsh hills at or above 300m and below 400m in height with 20m or more and below 30m of drop. The list is authored by Myrddyn Phillips, with the Introduction to the list and the renaming of it appearing on Mapping Mountains on the 13th May 2017.
The name this hill is listed by is Llanbradach Tip and as its name implies the hill is the result of mine spoil and it is the central of three pyramidal tips, 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 B4263 road to its south-west and the A469 road and the Afon Rhymni (Rhymney River) to its east, and has the small community of Llanbradach towards its south-east.
When the original 300m height band of Welsh P30 hills were published on Geoff Crowder’s v-g.me website this hill was not included in the Hills to be surveyed sub list as it was thought not to meet the criteria then used; however this sub list has now been standardised and interpolated heights and drop values also included in the main P30 and the accompanying sub list.
When this list was standardised and interpolated heights also included the area surrounding this hill was re-assessed but as the Ordnance Survey 1:25,000 Explorer map shows the hill to have no contours and the 1:50,000 Landranger map shows the hill with two ring contours its drop value was difficult to estimate.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
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| Extract from the Ordnance Survey 1:50,000 Landranger 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 addition of this hill to Sub-Trichant status is due to LIDAR analysis, resulting in a 338.0m summit height and a 310.0m bwlch height, with these values giving this hill 28.0m of drop which is sufficient for it to be classified as a Sub-Trichant.
The full details for the hill are:
Group: Cymoedd Gwent
Name: Llanbradach Tip
OS 1:50,000 map: 171
Summit Height: 338.0m (LIDAR)
Summit Grid Reference: ST 13939 91311 (LIDAR)
Bwlch Height: 310.0m (LIDAR)
Bwlch Grid Reference: ST 13887 91328 (LIDAR)
Drop: 28.0m (LIDAR)
Myrddyn Phillips (July 2019)
Pen y Bigil (SH 576 621) – Sub-Trichant reclassified to Trichant (23rd reclassification)
Survey post for Pen y Bigil
Significant Height Revisions post for Pen y Bigil
There has been confirmation of a reclassification to a hill that is listed in the Y Trichant, with the summit height, bwlch height and its location, and status of the hill initially confirmed by LIDAR analysis and subsequently by a summit survey with the Trimble GeoXH 6000 which were conducted by Myrddyn Phillips, with the latter taking place on the 6th October 2018.
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| Pen y Bigil (SH 576 621) |
The criteria for the list that this hill reclassification applies to are:
Y Trichant – Welsh hills at or above 300m and below 400m in height that have 30m minimum drop, with an accompanying sub list entitled the Sub-Trichant with the criteria for this sub category being all Welsh hills at or above 300m and below 400m in height with 20m or more and below 30m of drop. The list is authored by Myrddyn Phillips, with the Introduction to the list and the renaming of it appearing on Mapping Mountains on the 13th May 2017.
The name of the hill is Pen y Bigil and it is adjoined to the Glyderau group of hills, which are situated in the north-western part of North Wales (Region A, Sub-Region A1), and it has the A4244 road to its north-west and the A4086 road and Llyn Padarn to its south, and has the villages of Deiniolen towards the north and Llanberis towards the south.
When the original 300m height band of Welsh P30 hills were published on Geoff Crowder’s v-g.me website this hill was included in the Hills to be surveyed sub list as it was thought not to meet the criteria then used for the main P30 list; however this sub list has now been standardised and interpolated heights and drop values also included in the main P30 and the accompanying sub list.
When this list was standardised and interpolated heights also included this hill was listed with an estimated c 33m of drop, based on an estimated c 326m summit height and an estimated c 293m bwlch height, with each based on interpolation of 5m contouring on the contemporary 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 Ordnance Survey 1:25,000 historical map and the series of Six-Inch maps became available online, the former has a 1081ft height and the latter has a 1080ft height given to this hill’s summit, these heights equate to 329m in metric, and when coupled with the c 293m estimated bwlch height gives this hill c 36m of drop.
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| Extract from the Ordnance Survey series of Six-Inch maps |
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| Extract from the Ordnance Survey 1:25,000 historical map |
However, it was not until LIDAR became available that the details for this hill were next 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 the area of this hill’s bwlch has a road cutting running across it in the valley to valley direction it was not until examining LIDAR that the remaining natural bwch could be pinpointed.
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| LIDAR image of Pen y Bigil |
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| The road cutting splicing through the area of this hill's bwlch |
The confirmation of the reclassification of Pen y Bigil to Y Trichant status is due to LIDAR analysis and a subsequent survey with the Trimble GeoXH 6000 conducted by Myrddyn Phillips, resulting in a 331.0m summit height and an 292.6m bwlch height, with these values giving this hill 38.4m of drop which is sufficient for it to be classified as a Trichant.
The full details for the hill are:
Group: Glyderau
Name: Pen y Bigil
OS 1:50,000 map: 114, 115
Summit Height: 331.0m (converted to OSGM15)
Summit Grid Reference: SH 57600 62119
Bwlch Height: 292.6m (LIDAR)
Bwlch Grid Reference: SH 58014 62043 (LIDAR)
Drop: 38.4m (Trimble summit and LIDAR bwlch)
Myrddyn Phillips (March 2019)
Mapping Mountains - Hill Reclassifications - Y Trichant
Cefn Gwrhyd (SN 73108 08595 and SN 73110 08595) – Sub-Trichant reclassified to Trichant (22nd reclassification)
There has been a reclassification to the list of Y Trichant – The 300m Hills of Wales, with the summit height, bwlch height and their locations, the drop and status of the hill derived from LIDAR analysis conducted by Myrddyn Phillips.
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| LIDAR image of Cefn Gwrhyd (SN 731 086) |
The criteria for the list that this addition applies to are:
Y Trichant – The 300m Hills of Wales – Welsh hills at or above 300m and below 400m in height that have 30m minimum drop, with an accompanying sub list entitled the Sub-Trichant, with the criteria for this sub category being all Welsh hills at or above 300m and below 400m in height with 20m or more and below 30m of drop. The list is authored by Myrddyn Phillips with the Introduction to the list and the renaming of it appearing on Mapping Mountains on the 13th May 2017, and the Introduction to the Mapping Mountains publication of the list subsequently appearing on the 1st January 2022.
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| Y Trichant - The 300m Hills of Wales by Myrddyn Phillips |
The name the hill is listed by is Cefn Gwrhyd, and it is adjoined to the Mynydd Du group of hills, which are situated in the southern part of South Wales (Region B, Sub-Region B5), and it is positioned with the A474 road to its west, the A4068 road to its north and the A4067 road to its south-east, and has the town of Pontardawe towards the south, and the villages of Brynaman towards the north and Ystalyfera towards the east.
When the original 300m height band of Welsh P30 hills were published on Geoff Crowder’s v-g.me website, this hill appeared in the accompanying Hills to be surveyed sub list as it did not meet the criteria then used for the main P30 list.
When the sub list was standardised, and interpolated heights and drop values also included the details for this hill were re-evaluated and it was listed an estimated c 29m of drop, based on an estimated c 303m summit height and an estimated c 274m bwlch height, with each based on interpolation of 10m contouring.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
Since the original publication of the Welsh P30 lists on Geoff Crowder’s v-g.me website 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.
The details for this hill were re-assessed when the Ordnance Survey Vector Map Local hosted on the Geograph website and which was entitled the Interactive Coverage Map became available online. This mapping had many spot heights not on other publicly available Ordnance Survey maps and for this hill it had a 304m summit spot height and a 275m bwlch spot height, with these values giving this hill 29m of drop.
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| Extract from the Ordnance Survey Interactive Coverage Map hosted on the Geograph website showing the summit spot height |
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| Extract from the Ordnance Survey Interactive Coverage Map hosted on the Geograph website showing the spot height on the area of this hill's bwlch |
However, it was not until LIDAR became available that the details for this hill could be accurately re-assessed. The LIDAR (Light Detection & Ranging) technique produced highly accurate height data that is now freely available for much of England and Wales.
Therefore, the reclassification of this hill from Sub-Trichant status is due to LIDAR analysis, resulting in a 305.5m summit height and a 274.8m bwlch height, with these values giving this hill 30.7m of drop, which is sufficient for it to be classified as a Trichant.
The full details for the hill are:
Group: Mynydd Du
Name: Cefn Gwrhyd
OS 1:50,000 map: 160
Summit Height: 305.5m (LIDAR)
Summit Grid Reference: SN 73107 08600 and SN 73109 08601 (LIDAR)
Bwlch Height: 274.8m (LIDAR)
Bwlch Grid Reference: SN 73885 09967 (LIDAR)
Drop: 30.7m (LIDAR)
Myrddyn Phillips (March 2019)
Mapping Mountains - Hill Reclassifications - Y Trichant
Cwm Faerdy Bank (SO 078 695) – Sub-Trichant reclassified to Trichant (21st reclassification)
Survey post for Cwm Faerdy Bank
Significant Name Changes post for Cwm Faerdy Bank
There has been confirmation of a reclassification to the list of Y Trichant, with this initiated from LIDAR analysis and then confirmed by a Trimble GeoXH 6000 survey conducted by Myrddyn Phillips, with the lattet taking place on the 10th July 2018.
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| Cwm Faerdy Bank (SO 078 695) |
The criteria for the listing that this reclassification applies to are:
Y Trichant – Welsh hills at or above 300m and below 400m in height that have 30m minimum drop, with an accompanying sub list entitled the Sub-Trichant with the criteria for this sub category being all Welsh hills at or above 300m and below 400m in height with 20m or more and below 30m of drop. The list is authored by Myrddyn Phillips, with the Introduction to the list and its renaming appearing on Mapping Mountains on the 13th May 2017.
When the original Welsh P30 hills were published on Geoff Crowder’s v-g.me website this hill appeared in the accompanying Hills to be surveyed sub list as it did not meet the criteria then used for the main P30 list; however this sub list has now been standardised and interpolated heights also included in the main P30 and the accompanying sub list.
When this list was standardised and interpolated heights also included this hill was listed with an estimated c 30m of drop, based on the 302m spot height that appears on the Ordnance Survey 1:25,000 Explorer map and an estimated bwlch height of c 372m based on interpolation of bwlch contouring between 270m – 280m. These details were re-examined when the Ordnance Survey Interactive Coverage Map hosted on the Geograph website became available online and the drop value was then amended to c 31m.
The name of the hill is Cwm Faerdy Bank, and this was derived from local enquiry, and it is adjoined to the Pegwn Mawr range of hills which are situated in the north-eastern part of Mid and West Wales (Region B, Sub-Region B1), and it is positioned with the Clywedog Brook to its west and the Afon Ieithon (River Ithon) to its east, and has the small community of Abaty Cwm-hir (Abbeycwmhir) towards the north-west.
If wanting to visit the summit of the hill permission to do so should be sought as it is not a part of designated open access land, for those wishing to do so a public footpath approaches the hill from the north and east with the continuation of a track from where these footpaths meet leading toward the summit of the hill.
The confirmation of the reclassification of Cwm Faerdy Bank to Y Trichant status is due to LIDAR analysis conducted by Myrddyn Phillips. 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 Cwm Faerdy Bank |
The LIDAR analysis gives the hill the following details:
Name: Cwm Faerdy Bank
Summit Height: 302.2m
Summit Grid Reference: SO 07843 69513
Bwlch Height: 269.8m
Bwlch Grid Reference: SO 08305 69665
Drop: 32.3m
Therefore, the 302.2m LIDAR analysis for the summit position at SO 07843 69513 and the 269.8m LIDAR analysis for the bwlch position at SO 08305 69665 gives this hill 32.3m of drop, with the details from the Trimble GeoXH 6000 survey being 302.3m (converted to OSGM15) summit at SO 07842 69512 and 269.9m (converted to OSGM15) bwlch at SO 08304 69664, giving this hill 32.4m of drop which confirms its Trichant status.
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| The Trimble GeoXH 6000 gathering data at the summit of Cwm Faerdy Bank |
The full details for the hill are:
Group: Pegwn Mawr
Name: Cwm Faerdy Bank
OS 1:50,000 map: 136, 147
Summit Height: 302.3m (converted to OSGM15)
Summit Grid Reference: SO 07842 69512
Bwlch Height: 269.9m (converted to OSGM15)
Bwlch Grid Reference: SO 08304 69664
Drop: 32.4m (converted to OSGM15)
Mapping Mountains - Hill Reclassifications - Y Trichant
Allt y Genlli (SN 985 950) – Trichant reinstated to Sub-Trichant (2oth reclassification)
There has been a reclassification to the listing of Y Trichant due to a survey with a Leica GS15 conducted by John Barnard, Chris Crocker and Graham Jackson. Y Trichant is the title for the list of 300m hills of Wales and takes in all Welsh hills at or above 300m and below 400m in height that have a minimum 30m of drop, with the introduction to the re-naming of this list appearing on MappingMountains on the 13th May 2017.
Accompanying the main Y Trichant list is a category of sub hills entitled the Sub-Trichant, the criteria for Sub-Trichant status being all Welsh hills at or above 300m and below 400m in height that have 20m or more and below 30m of drop.
The name of the hill is Allt y Genlli and prior to the survey with the Leica GS15 the hill was listed with 73.2m of drop, based on a 398.9m summit and 325.7m bwlch, with these values obtained from LIDAR analysis. Its adjacent peak of Mynydd Garth Pwt was also analysed using LIDAR resulting in a 30.5m drop, based on a 397.8m summit and 367.3m bwlch. As LIDAR gave Allt y Genlli as higher their respective bwlch positions and heights were swapped resulting in Allt y Genlli being reclassified to a Trichant. The survey with the Leica GS15 has now reversed this classification to pre LIDAR analysis.
The hill is a part of the Pumlumon range with its Cardinal Hill being Bryn Amlwg (SN 921 973) and is placed in the Region of Mid and West Wales (Region B, Sub-Region B2). The hill is situated to the south of the A 470 and is positioned between the small communities of Carno to its west north-west and Clatter to its east.
Although the upper section of the hill is a part of designated open access land it is also immersed in conifer plantation. The summit of the hill is encircled by a forest track and for those determined souls who wish to visit; an approach from the north using this track may be the best option.
The survey with the Leica GS15 resulted in a summit height of 395.76m and a bwlch height of 367.05m, with these values giving this hill 28.7m of drop, which is insufficient for its retention as a Trichant.
The full details for the two hills are:
Cardinal Hill: Bryn Amlwg
Name: Allt y Genlli
Summit Height: 395.8m
OS 1:50,000 map: 136
Summit Grid Reference: SN 98508 95041
Drop: 28.7m
Cardinal Hill: Bryn Amlwg
Name: Mynydd Garth Pwt
Summit Height: 397.8m
OS 1:50,000 map: 136
Summit Grid Reference: SN 98154 94173
Drop: 72.1m
My thanks to John Barnard, Chris Crocker and Graham Jackson for bringing the survey result of this hill to my attention
Myrddyn Phillips (May 2018)
Mapping Mountains - Hill Reclassifications - Y Trichant
Carneddau (SO 076 543) – Sub-Trichant reclassified to Trichant (19th reclassification)
Survey post for Carneddau
Significant Name Change post for Carneddau
There has been a confirmation of a Hill Reclassification to the listing of Y Trichant, with the summit height, drop and status of the hill being confirmed by a Trimble GeoXH 6000 survey which took place on the 6th October 2017.
The criteria for the listing this hill reclassification affects are:
Y Trichant – Welsh hills at and above 300m and below 400m in height that have 30m minimum drop, with an accompanying sub category entitled the Sub-Trichant consisting of all Welsh hills at and above 300m and below 400m in height that have 20m and more and below 30m of drop. The list is authored by Myrddyn Phillips and the Introduction to the list and its re-naming and publication history was published on Mapping Mountains on the 13th May 2017.
The name of the hill is the Carneddau and it is adjoined to the Fforest Glud range of hills which are situated in the eastern part of Mid and West Wales (Region B, Sub-Region B1), and the hill is positioned between the town of Llanfair-ym-Muallt to its south-west and the small community of Hundred House to its east.
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| Carneddau (SO 076 543) |
The hill was listed in the sub category that accompanied the original Welsh P30 lists published on Geoff Crowder’s v-g.me website, when this sub category was standardised and drop values also added this hill was reclassified to a P30 with c 30m of drop, this value was later amended when the Ordnance Survey Interactive Coverage Map hosted on the Geograph website became available online as the bwlch was shown with a 345m spot height, which when coupled with the 376m summit spot height on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer maps gave this hill 31m of drop.
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| Extract from the Ordnance Survey Interactive Coverage Map hosted on the Geograph website |
The upper section of the hill forms a part of designated open access land with public footpaths approaching it from the north, south and east, with each giving access from the convenience of a relatively high minor lane.
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| The Trimble GeoXH 6000 gathering data at the summit of the Carneddau (SO 076 543) |
The survey result obtained with the Trimble GeoXH 6000 produced a summit height of 375.0m (converted to OSGM15) and a bwlch height of 344.7m (converted to OSGM15), with these values giving this hill 30.3m of drop, which confirms this hill’s reclassification to Trichant status.
The full details for the hill are:
Group: Fforest Glud
Name: Carneddau
Summit Height: 375.0m (converted to OSGM15)
OS 1:50,000 map: 147
Summit Grid Reference: SO 07652 54311
Drop: 30.3m (converted to OSGM15)
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| The Trimble GeoXH 6000 gathering data at the critical bwlch of the Carneddau (SO 076 543) |
For details on the survey that confirmed this hill’s reclassification to Trichant status
Myrddyn Phillips (December 2017)
Mapping Mountains - Hill Reclassifications - Y Trichant
Bwlchau Bank (SO 117 587)
Survey post for Bwlchau Bank
Significant Name Changes post for Bwlchau Bank
There has been a confirmation of a Hill Reclassification to the listing of Y Trichant, with the summit height, drop and status of the hill being confirmed by a Trimble GeoXH 6000 survey which took place on the 3rd October 2017.
The criteria for the listing this hill reclassification affects are:
Y Trichant – Welsh hills at and above 300m and below 400m in height that have 30m minimum drop, with an accompanying sub category entitled the Sub-Trichant consisting of all Welsh hills at and above 300m and below 400m in height that have 20m and more and below 30m of drop. The list is authored by Myrddyn Phillips and the Introduction to the list and its re-naming and publication history was published on Mapping Mountains on the 13th May 2017.
The name of the hill is Bwlchau Bank and it is adjoined to the Fforest Glud range of hills which are in the eastern part of Mid and West Wales (Region B, Sub-Region B1), and the hill is positioned between the town of Llandrindod (Llandrindod Wells) to its west north-west and the small community of Hundred House to its south.
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| Bwlchau Bank (SO 117 587) |
The hill was listed in the sub category that accompanied the original Welsh P30 lists published on Geoff Crowder’s v-g.me website, when this sub category was standardised and drop values also added this hill was reclassified to a P30 with c 33m of drop, this value was later amended when the Ordnance Survey Interactive Coverage Map hosted on the Geograph website became available online as the bwlch was shown with a 317m spot height, which when coupled with the 348m summit spot height on the Ordnance Survey 1:25,000 Explorer map gave this hill 31m of drop.
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| Extract from the Ordnance Survey Interactive Coverage Map hosted on the Geograph website |
As the summit of the hill is not on designated open access land permission to visit should be sought, for those wishing to do so there is easy access to the high point of the hill from its north-west, with the convenience of a minor lane giving access to a small mature conifer plantation adjacent to a field which leads to the summit.
The survey result obtained with the Trimble GeoXH 6000 produced a summit height of 348.3m (converted to OSGM15) and a bwlch height of 316.6m (converted to OSGM15), with these values giving this hill 31.6m of drop, which confirms this hill’s reclassification to Trichant status.
The full details for the hill are:
Group: Fforest Glud
Name: Bwlchau Bank
Summit Height: 348.3m (converted to OSGM15)
OS 1:50,000 map: 148
Summit Grid Reference: SO 11770 58788
Drop: 31.6m (converted to OSGM15)
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| The Trimble GeoXH 6000 gathering data at the summit of Bwlchau Bank |
For details on the survey that confirmed this hill’s reclassification to Trichant status
Myrddyn Phillips (December 2017)
Mapping Mountains - Hill Reclassifications - Y Trichant
Mynydd yr Heol (SO 107 601)
Survey post for Mynydd yr Heol
Significant Height Revisions post for Mynydd yr Heol
There has been a Hill Reclassification to the listing of Y Trichant due to a survey with the Trimble GeoXH 6000, with the survey that resulted in this hill reclassification taking place on the 3rd October 2017.
The criteria for the listing this hill reclassification affects are:
Y Trichant – All Welsh hills at and above 300m and below 400m in height that have 30m minimum drop. With an accompanying sub category entitled the Sub-Trichant consisting of all Welsh hills at and above 300m and below 400m in height that have 20m and more and below 30m of drop. The list is authored by Myrddyn Phillips and the Introduction to the list and its re-naming was published on Mapping Mountains on the 13th May 2017.
The name of the hill is Mynydd yr Heol and it is situated in the Fforest Glud range of hills which are in the eastern part of Mid and West Wales (Region B, Sub-Region B1), and the hill is positioned between the town of Llandrindod (Llandrindod Wells) to its west and the small community of Hundred House to its south.
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| Mynydd yr Heol (SO 107 601) |
The hill was listed in the sub category that accompanied the original Welsh P30 lists when published on Geoff Crowder’s v-g.me website, this sub category has now been standardised and drop values also added, this hill was subsequently listed with 27m of drop based on the 382m summit spot height that appears on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer maps and a 355m bwlch spot height that appears on the Ordnance Survey Interactive Coverage Map hosted on the Geograph website.
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| Extract from the Ordnance Survey Interactive Coverage Map hosted on the Geograph website |
As the summit of the hill is not on designated open access land permission to visit should be sought, for those wishing to do so the nearest public footpath is south of the summit and passes over its bwlch in a west – east direction. However, the easiest and most convenient ascent is from the east following a green track up the hill from the convenience of a minor lane.
The survey with the Trimble GeoXH 6000 produced a summit height of 386.8m (converted to OSGM15) and a bwlch height of 355.6m (converted to OSGM15), with these values giving this hill 31.2m of drop, which confirms this hill’s reclassification to Trichant status and the total in the Y Trichant will be updated accordingly.
The full details for the hill are:
Cardinal Hill: Gilwern Hill
Summit Height: 386.8m (converted to OSGM15)
Name: Mynydd yr Heol
OS 1:50,000 map: 148
Summit Grid Reference: SO 10793 60177
Drop: 31.2m (converted to OSGM15)
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| Gathering data with the Trimble GeoXH 6000 at the summit of Mynydd yr Heol |
Myrddyn Phillips (December 2017)
Bwlch y Cefn Bank (SO 123 608) – Pedwar reclassified to Trichant (16th reclassification)
Survey post for Bwlch y Cefn Bank
There has been a reclassification to the listing of Y Trichant due to analysis of LIDAR data by Aled Williams and subsequently confirmed via a survey with the Trimble GeoXH 6000. Y Trichant is the title for the hills in the 300m height band of the Twmpau (thirty welsh metre prominences and upward) and takes in all Welsh hills at or above 300m and below 400m in height that have a minimum 30m of drop, with the introduction to the re-naming of this list appearing on Mapping Mountains on the 13th May 2017.
Prior to analysis of LIDAR data this hill was listed as a Pedwar with c 52m of drop based on the 400m summit spot height that appears on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer maps and an estimated bwlch height of c 348m based on interpolation of bwlch contouring between 340m – 350m. The criteria for Pedwar status are all Welsh hills at or above 400m and below 500m in height that have a minimum 30m of drop, the list is a joint compilation between Myrddyn Phillips and Aled Williams and it commenced publication on Mapping Mountains on the 30th January 2017.
The name of the hill is Bwlch y Cefn Bank and it is situated in the Elfael range of hills with its Cardinal Hill being Gilwern Hill (SO 098 582) and is placed in the Region of Mid and West Wales (Region B, Sub-Region B1). The hill is positioned above the A 44 road which is to its east and to its north, and the Afon Ieithon (River Ithon) which is to its north-west, with the small community of Llandegley to the north north-east of the hill.
As the summit of the hill is not a part of designated open access land permission to visit should be sought, for those wishing to do so the land to the north-east and the south-west of the hill is a part of designated open access land, and a public footpath crosses between each just to the south-east of this hill’s summit.
The reclassification of Bwlch y Cefn Bank to Trichant status is due to the analysis of LIDAR data by Aled Williams. LIDAR (Light Detection & Ranging) is highly accurate height data that is now freely available for much of England and Wales.
Aled’s analysis of LIDAR data gives the hill the following details:
Bwlch y Cefn Bank
Summit Height: 399.0m
Summit Grid Reference: SO 12367 60871
Bwlch Height: 347.1m
Bwlch Grid Reference: SO 12752 60893
Drop: 51.9m
Therefore, the 399.0m LIDAR data produced for the summit position at SO 12367 60871 and the 347.1m LIDAR data produced for the bwlch position at SO 12752 60893 gives this hill 51.9m of drop, and as the summit height is below 400m and in the 300m height band it is sufficient for this hill to be reclassified to Trichant status, with the details from the Trimble GeoXH 6000 survey being 399.9m (converted to OSGM15) summit at SO 12369 60880 and 347.2m (converted to OSGM15) bwlch at SO 12752 60893, giving this hill a summit height below 400m.
The full details for the hill are:
Cardinal Hill: Gilwern Hill
Summit Height: 399.9m (converted to OSGM15)
Name: Bwlch y Cefn Bank
OS 1:50,000 map: 148
Summit Grid Reference: SO 12369 60880
Drop: 52.7m (converted to OSGM15)
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| Bwlch y Cefn Bank (SO 123 608) is now included in the Y Trichant listing of hills |
My thanks to Aled Williams for sending the details of this hill to me
For details on the survey that confirmed this hill's Trichant status
Myrddyn Phillips (September 2017)
Myrddyn Phillips (September 2017)
Mapping Mountains - Hill Reclassifications - Y Trichant
Penmaen Mawr (SH 698 755) Sub-Trichant addition (15th reclassification)
Survey post for Penmaen Mawr
Significant Height Revisions post for Penmaen Mawr
There has been an addition to the listing of Y Trichant initiated by a survey with the Trimble GeoXH 6000, with subsequent confirmation through analysis of LIDAR data by Aled Williams. Y Trichant is the title for the hills in the 300m height band of the Twmpau (thirty welsh metre prominences and upward) and takes in all Welsh hills at or above 300m and below 400m in height that have a minimum 30m of drop, with the introduction to the re-naming of this list appearing on Mapping Mountains on the 13th May 2017.
The details relating to this hill’s addition as a Sub-Trichant are retrospective as its new classification was dependent upon a survey with the Trimble GeoXH 6000 which was conducted on the 14th July 2016.
The hill did not appear in the sub category that accompanied the original Welsh P30 lists when published on Geoff Crowder’s v-g.me website, this sub category has now been standardised and named the Sub-Trichant and comprises all Welsh hills at or above 300m and below 400m in height with 20m or more and below 30m of drop.
The hill was not classified prior to the survey with the Trimble as much of the hill has been quarried and as is the norm in such circumstances there is a lack of uppermost contour lines on current Ordnance Survey maps. But at one stage it was a part of a relatively substantial hill that had a prominence in excess of 100m and a 1,550ft (472m) summit map height shown on the Ordnance Survey Popular and New Popular One-Inch maps, with this height also appearing on the Ordnance Survey Six-Inch map published in 1888, and therefore it would have met the criteria specified for inclusion to the Humps and the main Y Pedwarau listings. The subsequent quarrying has produced two distinct summits with the details given in this post relating to the higher of the two summits that are both known by the same name. The hill no longer meets the qualification for these two listings as its summit has been quarried and current Ordnance Survey maps only give it an uppermost 370m contour line. However, quarried areas are usually given no contour lines on Ordnance Survey maps indicating that the ground is or has been in flux, and photographic and map study by Aled indicated that the remaining high point was substantially higher than 370m.
The name of the hill is Penmaen Mawr and it is a part of the Carneddau range with its Cardinal Hill being Tal y Fan (SH 729 726) and is placed in the Region of North Wales (Region A, Sub-Region A1). The hill is situated to the south of the A 55 road and is positioned between the towns of Llanfairfechan to its west and Penmaenmawr to its east, with the latter taking its name from the hill.
The hill can be easily accessed from a minor road to the south of the summit that reaches over 260m in height, a public footpath heads north from just below the high point of this minor road and joins a track designated a bridleway that contours around the southern slopes of the upper section of the hill. A large section of the land above the bridleway is designated open access land and the summit of Penmaen Mawr is close to this.
The full details for the hill are:
Cardinal Hill: Tal y Fan
Summit Height: 390.4m (converted to OSGM15)
Name: Penmaen Mawr
OS 1:50,000 map: 115
Summit Grid Reference: SH 69865 75523
Drop: 26.9m (converted to OSGM15)
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| Penmaen Mawr (SH 698 755) is now included in the listing of Sub-Trichant hills |
Myrddyn Phillips (September 2017)
Mapping Mountains - Hill Reclassifications - Y Trichant
Curnau Mawr (SN 751 750) – Sub-Trichant addition (14th reclassification)
Survey post for Curnau Mawr
There has been an addition to the listing of Y Trichant due to analysis of LIDAR data by Aled Williams and subsequently confirmed via a survey with the Trimble GeoXH 6000. Y Trichant is the title for the hills in the 300m height band of the Twmpau (thirty welsh metre prominences and upward) and takes in all Welsh hills at or above 300m and below 400m in height that have a minimum 30m of drop, with the introduction to the re-naming of this list appearing on Mapping Mountains on the 13th May 2017.
The hill did not appear in the sub category that accompanied the original Welsh P30 lists when published on Geoff Crowder’s v-g.me website, this sub category has now been standardised and named the Sub-Trichant and comprises all Welsh hills at or above 300m and below 400m in height with 20m or more and below 30m of drop.
Prior to analysis of LIDAR data the hill was not classified but it was catalogued with c 16m of drop based on an estimated c 390m summit height and an estimated c 374m bwlch height, the latter height based on interpolation of bwlch contouring between 370m – 380m.
The hill is a part of the Elenydd range with its Cardinal Hill being Pen y Garn (SN 798 771) and is placed in the Region of Mid and West Wales (Region B, Sub-Region B2). The hill is situated with the B 4574 to its north and the B 4343 to its west and is positioned between the small communities of Pontarfynach (Devil’s Bridge) to its north-west and Cwmystwyth to its east south-east.
For those wishing to visit the summit the whole upper section of the hill is a part of designated open access land, and this has immediate access from the B 4343 to the west or from a public footpath from the same road that intersects with the open access lane.
The name of the hill is Curnau Mawr and its addition to Sub-Trichant status is due to the analysis of LIDAR data by Aled Williams. LIDAR (Light Detection & Ranging) is highly accurate height data that is now freely available for much of England and Wales.
Aled’s analysis of LIDAR data gives the hill the following details:
Curnau Mawr
Summit Height: 391.4m
Summit Grid Reference: SN 75155 75007
Bwlch Height: 369.8m
Bwlch Grid Reference: SN 75343 74906
Drop: 21.6m
Therefore, the 391.4m LIDAR data produced for the summit position at SN 75155 75007 and the 369.8m LIDAR data produced for the bwlch position at SN 75343 74906 gives this hill 21.6m of drop which is sufficient for its inclusion as a Sub-Trichant, with the details from the Trimble GeoXH survey being 391.4m (converted to OSGM15) summit at SN 75154 75006 and 369.8m (converted to OSGM15) bwlch at SN 75342 24906, giving this hill 21.6m of drop.
The full details for the hill are:
Cardinal Hill: Pen y Garn
Summit Height: 391.4m (converted to OSGM15 Trimble GeoXH 6000)
Name: Curnau Mawr
OS 1:50,000 map: 135, 147
Summit Grid Reference: SN 75154 75006
Drop: 21.6m
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| Curnau Mawr (SN 751 750) confirmed as a Sub-Trichant |
My thanks to Aled Williams for sending the details of this hill to me
Myrddyn Phillips (July 2017)
Mapping Mountains - Hill Reclassifications - Y Trichant
Ffridd Fawr (SJ 166 274) – Sub-Trichant addition (13th reclassification)
Survey post for Ffridd Fawr
Significant Name Changes post for Ffridd Fawr
There has been a confirmation of an addition to the listing of Y Trichant due to a survey with the Trimble GeoXH 6000. Y Trichant is the title for the hills in the 300m height band of the Twmpau (thirty welsh metre prominences and upward) and takes in all Welsh hills at or above 300m and below 400m in height that have a minimum 30m of drop, with the introduction to the re-naming of this list appearing on Mapping Mountains on the 13th May 2017.
The hill did not appear in the sub category that accompanied the original Welsh P30 lists when published on Geoff Crowder’s v-g.me website, this sub category has now been standardised and named the Sub-Trichant and comprises all Welsh hills at or above 300m and below 400m in height with 20m or more and below 30m of drop.
When the sub list was standardised and drop values also added the hill was listed with c 22m of drop, based on the 335m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and an estimated bwlch height of c 313m based on interpolation of bwlch contours between 310m – 320m.
The name of the hill is Ffridd Fawr which was derived from local enquiry and it is situated in the Y Berwyn group of hills and is placed in the Region of North Wales (Region A, Sub-Region A4) with its Cardinal Hill being Craig Berwyn (SJ 071 323). The hill is positioned above the small community of Moelfre which is to the east north-east of the hill, and between Llanrhaeadr-ym-Mochnant to the west south-west and Llansilin towards the east.
As the hill is not a part of designated open access land, permission to visit should be sought, for those wishing to do so a public footpath approaches the hill from its north-west.
The survey with the Trimble GeoXH 6000 produced a summit height of 335.1m (converted to OSGM15) and a bwlch height of 312.4m (converted to OSGM15), with these values giving this hill 22.7m of drop, which confirms its addition to Sub-Trichant status and the total in the Y Trichant and the Twmpau will be updated accordingly.
The full details for the hill are:
Cardinal Hill: Craig Berwyn
Summit Height: 335.1m (converted to OSGM15)
Name: Ffridd Fawr
OS 1:50,000 map: 125
Summit Grid Reference: SJ 16688 27439
Drop: 22.7m (converted to OSGM15)
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| Ffridd Fawr (SJ 166 274) confirmed as an addition to the Sub-Trichant |
Myrddyn Phillips (July 2017)
Mapping Mountains - Hill Reclassifications - Y Trichant
Comins (SJ 174 282) – Sub-Trichant reclassified to Trichant (12th reclassification)
Survey post for Comins
Significant Name Changes post for Comins
There has been a confirmation of a reclassification to the listing of Y Trichant due to a survey with the Trimble GeoXH 6000 and subsequent LIDAR analysis. Y Trichant is the title for the hills in the 300m height band of the Twmpau (thirty welsh metre prominences and upward) and takes in all Welsh hills at or above 300m and below 400m in height that have a minimum 30m of drop, with the introduction to the re-naming of this list appearing on Mapping Mountains on the 13th May 2017.
The hill was listed in the sub category that accompanied the original Welsh P30 lists when published on Geoff Crowder’s v-g.me website, this sub category has now been standardised and named the Sub-Trichant and comprises all Welsh hills at or above 300m and below 400m in height with 20m or more and below 30m of drop.
When the sub list was standardised and drop values also added the hill was reclassified to the main Y Trichant list with c 31m of drop which was later amended to c 34m of drop, based on the 376m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and an estimated bwlch height of c 342m based on interpolation of bwlch contours between 340m – 350m.
The name of the hill is Comins which was derived from local enquiry and it is situated in the Y Berwyn group of hills and is placed in the Region of North Wales (Region A, Sub-Region A4) with its Cardinal Hill being Craig Berwyn (SJ 071 323). The hill is positioned above the small communities of Moelfre which is to its east north-east and Llansilin which is farther away to the hill’s east.
As the hill is not a part of designated open access land, permission to visit should be sought, for those wishing to do so an ascent on public footpaths either from the west or east connects with green tracks which ascend toward the summit.
The survey with the Trimble GeoXH 6000 produced a summit height of 376.1m, with LIDAR analysis giving a bwlch height of 341.2m, with these values giving this hill 34.8m of drop, which confirms its reclassification to Trichant status.
The full details for the hill are:
Cardinal Hill: Craig Berwyn
Summit Height: 376.1m (converted to OSGM15)
Name: Comins
OS 1:50,000 map: 125
Summit Grid Reference: SJ 17476 28210
Drop: 34.8m
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| Comins (SH 174 282) on left of photograph |
Myrddyn Phillips (July 2017)
Mapping Mountains - Hill Reclassifications - Y Trichant
Allt y Genlli (SN 985 950) – Sub-Trichant reclassified to Trichant (11th reclassification)
THIS HILL HAS SUBSEQUENTLY BEEN RE-INSTATED TO SUB-TRICHANT STATUS
The following details have been superseded by a survey conducted by John Barnard, Chris Crocker and Graham Jackson using a Leica GS15 with the result that this hill has been re-instated to Sub-Trichant status with 28.7m of drop.
Below is the Hill Reclassifications post prior to the Leica GS15 survey:The following details have been superseded by a survey conducted by John Barnard, Chris Crocker and Graham Jackson using a Leica GS15 with the result that this hill has been re-instated to Sub-Trichant status with 28.7m of drop.
There has been a reclassification to the listing of the Y Trichant due to analysis of LIDAR data by Aled Williams. Y Trichant is the title for the hills in the 300m height band of the Twmpau (thirty welsh metre prominences and upward) and takes in all Welsh hills at or above 300m and below 400m in height that have a minimum 30m of drop, with the introduction to the re-naming of this list appearing on Mapping Mountains on the 13th May 2017.
The hill was listed in the sub category that accompanied the original Welsh P30 lists when published on Geoff Crowder’s v-g.me website, this sub category has now been standardised and named the Sub-Trichant and comprises all Welsh hills at or above 300m and below 400m in height with 20m or more and below 30m of drop.
Prior to analysis of LIDAR data the hill was listed as a Sub-Trichant and its reclassification is dependent upon its adjacent southerly hill of Mynydd Garth Pwt, because of this the previously listed details of both hills based on map data are given below:
Allt y Genlli (previously listed as a Sub-Trichant)
Summit Height: 394m (OS 1:25,000 Explorer map)
Summit Grid Reference: SN 985 950
Bwlch Height: 367m (OS enlarged mapping hosted on the Geograph website)
Bwlch Grid Reference: SN 983 944
Drop: 27m
Mynydd Garth Pwt (listed as a Trichant)
Summit Height: 397m (OS 1:50,000 Landranger and 1:25,000 Explorer maps)
Summit Grid Reference: SN 981 941
Bwlch Height: c 325m
Bwlch Grid Reference: SN 973 941
Drop: c 72m
The hill is a part of the Pumlumon range of hills with its Cardinal Hill being Bryn Amlwg (SN 921 973) and is placed in the Region of Mid and West Wales (Region B, Sub-Region B2). The hill is situated to the south of the A 470 and is positioned between the small communities of Carno to its west north-west and Clatter to its east.
The upper part of the hill is a part of designated open access land, however it is also immersed in conifer plantation with its summit encircled by a forest track, and for those who wish to visit its high point an approach from the north using this track may be the best option.
The name of the hill is Allt y Genlli and its reclassification from Sub-Trichant to Trichant status is dependent upon its adjacent southerly hill of Mynydd Garth Pwt and the analysis of LIDAR data by Aled Williams. LIDAR (Light Detection & Ranging) is highly accurate height data that is now freely available for much of England and Wales.
Aled’s analysis of LIDAR data gives these two hills the following details:
Allt y Genlli
Summit Height: 398.9m
Summit Grid Reference: SN 98508 95042
Bwlch Height: 325.7m
Bwlch Grid Reference: SN 97387 94159
Drop: 73.2m
Mynydd Garth Pwt
Summit Height: 397.8m
Summit Grid Reference: SN 98154 94173
Bwlch Height: 367.3m
Bwlch Grid Reference: SN 98385 94438
Drop: 30.5m
Therefore, as the 398.9m LIDAR data produced for the summit position of Allt y Genlli at SN 98508 95042 is higher than the 397.8m LIDAR data produced for the summit position of Mynydd Garth Pwt at SN 98154 94173, the listed bwlch position of each hill is swapped as the lower bwlch is the critical bwlch for the higher of the two hills.
The full details for the two hills are:
Cardinal Hill: Bryn Amlwg
Summit Height: 398.9m (LIDAR data)
Name: Allt y Genlli
OS 1:50,000 map: 136
Summit Grid Reference: SN 98508 95042
Drop: 73.2m (LIDAR data)
Cardinal Hill: Bryn Amlwg
Summit Height: 397.8m (LIDAR data)
Name: Mynydd Garth Pwt
OS 1:50,000 map: 136
Summit Grid Reference: SN 98154 94173
Drop: 30.5m (LIDAR data)
My thanks to Aled Williams for sending the details of this hill to me.
Myrddyn Phillips (May 2017)
Mapping Mountains - Hill Reclassifications - Y Trichant
Penmaen Mawr (SH 702 756) – Sub-Trichant reclassified to Trichant (10th reclassification)
There has been a reclassification to the listing of the Y Trichant, this is the draft title for the hills in the 300m height band of the Twmpau (thirty welsh metre prominences and upward) due to analysis of LIDAR data by Aled Williams. The hill was previously surveyed with the Trimble GeoXH 6000 and included as a Sub-Trichant with 29.8m of drop. The criteria for Y Trichant being all Welsh hills 300m or more and below 400m in height with 30m minimum drop and the Sub-Trichant being all Welsh hills 300m or more and below 400m in height with 20m or more and below 30m of drop.
The hill was not classified prior to the survey with the Trimble as much of the hill has been quarried and as is the norm in such circumstances there is a lack of uppermost contour lines on current Ordnance Survey maps. But at one stage it was a part of a relatively substantial hill that had a prominence in excess of 100m and a 1,550ft (472m) summit map height shown on the Ordnance Survey Popular and New Popular One-Inch maps, with this height also appearing on the Ordnance Survey Six-Inch map published in 1888, and therefore it would have met the criteria specified for inclusion to the Humps and the Y Pedwarau listings. The subsequent quarrying has produced two distinct summits with the details given in this post relating to the lower of the two summits that are both known by the same name.
The hill is a part of the Carneddau range with its Cardinal Hill being Tal y Fan (SH 729 726) and is placed in the Region of North Wales (Region A, Sub-Region A1). The hill is situated to the south of the A 55 and is positioned between the towns of Llanfairfechan to its west and Penmaenmawr to its east, with the latter taking its name from the hill.
The hill can be easily accessed from a minor road to the south of the summit that reaches over 260m in height, a public footpath heads north from just below the high point of this minor road and joins a track which is marked as a bridleway that contours around the southern slopes of the upper section of the hill. A large section of land above the bridleway is designated open access and the summit of the lower of the two Penmaen Mawr hills is close to this.
The name of the hill is Penmaen Mawr and its reclassification from Sub-Trichant to Trichant status is due to analysis of LIDAR data by Aled Williams. LIDAR (Light Detection & Ranging) is highly accurate height data that is now freely available for much of England and Wales.
Aled’s analysis of LIDAR data gives the hill the following details:
Penmaen Mawr
Summit Height: 385.8m
Summit Grid Reference: SH 70292 75649
Bwlch Height: 354.5m
Bwlch Grid Reference: SH 70441 75241
Drop: 31.3m
Therefore, the 385.8m LIDAR data produced for the summit position at SH 70292 75649 and the 354.5m LIDAR data produced for the bwlch position at SH 70441 75241 gives this hill 31.3m of drop, which is sufficient for its reclassification to a Trichant, therefore the total in the Y Trichant and the Twmpau which will be updated accordingly.
The full details for the hill are:
Cardinal Hill: Tal y Fan
Summit Height: 385.8m (LIDAR data)
Name: Penmaen Mawr
OS 1:50,000 map: 115
Summit Grid Reference: SH 70292 75649
Drop: 31.3m (LIDAR data)
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| Penmaen Mawr (SH 702 756) now reclassified from a Sub-Trichant to a Trichant |
My thanks to Aled Williams for sending the details of this hill to me.
Myrddyn Phillips (May 2017)
Mapping Mountains - Hill Reclassifications - Y Trichant
Twyn y Ffald (SN 852 160) - Sub-Trichant addition (9th reclassification)
There has been an addition to the listing of the Y Trichant, this is the draft title for the hills in the 300m height band of the Twmpau (thirty welsh metre prominences and upward) due to analysis of LIDAR data by Aled Williams. With the criteria for Y Trichant being all Welsh hills 300m or more and below 400m in height with 30m minimum drop.
Accompanying the main Y Trichant list is a sub list entitled the Sub-Trichant. With the criteria for Sub-Trichant qualification being all Welsh hills at or above 300m and below 400m in height with 20m or more and below 30m of drop.
Prior to analysis of LIDAR data the hill was catalogued with c 19m of drop which was insufficient for it to be listed as a Sub-Trichant, this drop value was based on an estimated summit height of c 362m and an estimated bwlch height of c 343m, with the latter taken to land that forms a part of a disused quarry, and therefore the old connecting bwlch of this hill no longer exists.
The hill is adjoined to the Fforest Fawr group of hills with its Cardinal Hill being Fan Gyhirych (SN 880 191) and is placed in the Region of South Wales (Region C, Sub-Region C2), and is situated with the small community of Glyntawe to its north-west.
The hill can be accessed from the end of a minor road at Penwyllt and can be combined with higher hills to its east. However, the summit of this hill is not on open access land and it is positioned on the periphery of a disused quarry, therefore permission should be sought to visit, but with open access land relatively close towards the north-east, common sense should prevail and if wanting to visit the summit there is likely to be no objection to doing so.
The name of the hill is Twyn y Ffald and its addition to Sub-Trichant status is due to analysis of LIDAR data by Aled Williams. LIDAR (Light Detection & Ranging) is highly accurate height data that is now freely available for much of England and Wales.
Aled’s analysis of LIDAR data gives the hill the following details:
Twyn y Ffald
Summit Height: 368.7m
Summit Grid Reference: SN 85227 16034
Bwlch Height: 342.8m
Bwlch Grid Reference: SN 85541 16188
Drop: 25.9m
Therefore, the 368.7m LIDAR data produced for the summit position at SN 85227 16034 and the 342.8m LIDAR data produced for the bwlch position at SN 85541 16188 gives this hill 25.9m of drop, which is sufficient for its inclusion as a Sub-Trichant, therefore this hill is included in this sub category and the total in the Y Trichant and the Twmpau which will be updated accordingly.
The full details for the hill are:
Cardinal Hill: Fan Gyhirych
Summit Height: 368.7m (LIDAR data)
Name: Twyn y Ffald
OS 1:50,000 map: 160
Summit Grid Reference: SN 85227 16034
Drop: 25.9m (LIDAR data)
My thanks to Aled Williams for sending the details of this hill to me.
Myrddyn Phillips (April 2017)
Mapping Mountains - Hill Reclassifications - Y Trichant
Pt. 360.3m (SH 700 466) - Sub-Trichant addition (8th reclassification)
There has been an addition to the listing of Y Trichant, this is the draft title for the hills in the 300m height band of the Twmpau (thirty welsh metre prominences and upward) due to analysis of LIDAR data by Aled Williams. The criteria for Y Trichant being all Welsh hills 300m or more and below 400m in height with 30m minimum drop and the now standardised Sub-Trichant being all Welsh hills 300m or more and below 400m in height with 20m or more and below 30m of drop, with this hill being an addition to the Sub-Trichant category.
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| LIDAR image of Pt. 360.3m (SH 700 466) |
The hill is a contentious addition to the Sub-Trichant as it is a part of the Llechwedd Slate Mine and may be viewed by some as not being stable in nature and is described as a Tip (disused) on the Ordnance Survey enlarged mapping hosted on the Geograph website. As is the norm with such places it is not given any ring contours on current Ordnance Survey maps.
The hill is adjoined to the Arenig group with its Cardinal Hill being Manod Mawr (SH 724 446) and is placed in the Region of North Wales (Region A, Sub-Region A3), and it is situated above the town of Blaenau Ffestiniog which is to its south and has the A 470 road to its west.
As this hill is a part of a slate mine that is worked intermittently permission to visit should be sought, because of this no route to its summit is recommended.
The Point (Pt. 360.3m) notation is being used as I do not know an appropriate local or historical name for this hill, and its addition as a Sub-Trichant is due to analysis of LIDAR data by Aled Williams. LIDAR (Light Detection & Ranging) is highly accurate height data that is now freely available for much of England and Wales.
Aled’s analysis of LIDAR data gives the hill the following details:
Pt. 360.3m
Summit Height: 360.1m
Summit Grid Reference: SH 70071 46613
Bwlch Height: 332.2m
Bwlch Grid Reference: SH 70214 46654
Drop: 28.1m
Therefore, the 360.3m LIDAR data produced for the summit position at SH 70071 46613 and the 332.2m LIDAR data produced for the bwlch position at SH 70214 46654 gives this hill 28.1m of drop, which is sufficient for its inclusion as a Sub-Trichant, and the listings of Y Trichant and the Twmpau which will be updated accordingly.
The full details for the hill are:
Cardinal Hill: Manod Mawr
Summit Height: 360.3m (LIDAR)
Name: Pt. 360.3m
OS 1:50,000 map: 115
Summit Grid Reference: SH 70071 46613
Drop: 28.1m (LIDAR)
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| Pt. 360.3m (SH 700 466) a new addition to the Sub-Trichant |
My thanks to Aled Williams for sending the details of this hill to me.
Mapping Mountains - Hill Reclassifications - Y Trichant
Garreg Ddu (SH 701 462) - Trichant reclassified to Sub-Trichant (7th reclassification)
There has been a reclassification to the listing of Y Trichant, this is the draft title for the hills in the 300m height band of the Twmpau (thirty welsh metre prominences and upward) due to analysis of LIDAR data by Aled Williams. The hill was listed in the sub category that accompanied the original Welsh P30 lists when published on Geoff Crowder’s v-g.me website, with the criteria for Y Trichant being all Welsh hills 300m or more and below 400m in height with 30m minimum drop and the now standardised Sub-Trichant being all Welsh hills 300m or more and below 400m in height with 20m or more and below 30m of drop.
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| LIDAR image of Garreg Ddu (SH 701 462) |
When drop values were added to the Welsh P30 Master Lists this hill was given an estimated c 29m of drop, however this was re-evaluated and the hill was reclassified to Trichant status with c 30m of drop, this was based on the 348m summit spot height that appears on Ordnance Survey 1:25,000 Explorer maps and an estimated bwlch height of c 318m.
The hill is adjoined to the Arenig group of hills with its Cardinal Hill being Manod Mawr (SH 724 446) and is placed in the Region of North Wales (Region A, Sub-Region A3). The hill is situated between the town of Blaenau Ffestiniog to its immediate south and the Llechwedd Slate Mines to its immediate north.
The hill forms the southern barrier to the extensive slate mines that pre-dominate the landscape above and to the north of Blaenau Ffestiniog, and is situated on open access land, and can be accessed from the backstreets of the town leading to an old incline to the open hillside above.
The name of the hill is Garreg Ddu and its reclassification to Sub-Trichant status is due to analysis of LIDAR data by Aled Williams. LIDAR (Light Detection & Ranging) is highly accurate height data that is now freely available for much of England and Wales.
Aled’s analysis of LIDAR data gives the hill the following details:
Garreg Ddu
Summit Height: 348.2m
Summit Grid Reference: SH 70187 46223
Bwlch Height: 319.6m
Bwlch Grid Reference: SH 70187 46364
Drop: 28.6m
Therefore, the 348.2m LIDAR data produced for the summit position at SH 70187 46223 and the 319.6m LIDAR data produced for the bwlch position at SH 70187 46364 gives this hill 28.6m of drop, which is insufficient for its retention as a Trichant, therefore this hill is listed as a Sub-Trichant and the total in the Y Trichant and the Twmpau which will be updated accordingly.
The full details for the hill are:
Cardinal Hill: Manod Mawr
Summit Height: 348.2m (LIDAR)
Name: Garreg Ddu
OS 1:50,000 map: 115
Summit Grid Reference: SH 70187 46223
Drop: 28.6m (LIDAR)
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| Garreg Ddu (SH 701 462) is now reclassified to a Sub-Trichant |
My thanks to Aled Williams for sending the details of this hill to me.
Myrddyn Phillips (April 2017)
Mapping Mountains - Hill Reclassifications - Y Trichant
MRF Tip (SN 828 114) - Trichant addition (6th reclassification)
There has been an addition to the listing of the Y Trichant, these are the hills within the 300m height band of the Twmpau (thirty welsh metre prominences and upward) due to analysis of LIDAR data by Kevin McGovern and also independently by Aled Williams. The Y Trichant takes in all hills in Wales at or above 300m and below 400m in height that have a minimum drop of 30m.
Prior to analysis of LIDAR data the ridge known as Mynydd y Drum was listed with one summit, but due to opencast mining a further two summits have been created which are artificial and comprise the remains of waste spoil, the summit which this Hill Reclassifications post details is the lower of these two artificial hills, this has resulted in new bylchau heights and positions and also drop values for these three hills, all of these will be detailed in this and the previous and next Hill Reclassifications posts, with the name MRF Tip being found from local enquiry and the other two hills being Mynydd y Drum (SN 807 097) and Teisen Priodas (SN 820 108).
The hill is adjoined to the Fforest Fawr group with its Cardinal Hill being Fan Gyhirych (SN 880 191) and is placed in the Region of South Wales (Region C, Sub-Region C2), and it is positioned between the small communities of Abercraf (Abercrave) to the north-west and Y Coelbren towards the east.
The summit of the hill is situated within the Nant Helen Opencast Mine so permission to visit the high point should be sought, however it has open access land to its east and a little farther away to its south, and two public footpaths are marked on Ordnance Survey maps that head extremely close to the summit of this hill.
The name of the hill is MRF Tip and its reclassification to a Trichant is due to the analysis of LIDAR data by Kevin McGovern and also independently by Aled Williams. LIDAR (Light Detection & Ranging) is highly accurate height data that is now freely available for much of England and Wales.
Kevin’s analysis of LIDAR data gives the hill the following details:
MRF Tip
Summit Height: 311.8m (converted to OSGM15)
Summit Grid Reference: SN 82850 11432
Bwlch Height: 277.6m (converted to OSGM15)
Bwlch Grid Reference: SN 82186 11128
Drop: 34.2m
Therefore, the 311.8m LIDAR data produced for the summit position at SN 82850 11432 and the 277.6m LIDAR data produced for the bwlch position at SN 82186 11128 is sufficient for this hill to be classified as a Trichant with 34.2m of drop.
The full details for the hill are:
Cardinal Hill: Fan Gyhirych
Summit Height: 311.8m (LIDAR data, converted to OSGM15)
Name: MRF Tip
OS 1:50,000 map: 160
Summit Grid Reference: SN 82850 11432
Drop: 34.2m (LIDAR data, converted to OSGM15)
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| MRF Tip (SN 828 114) now listed as a Trichant |
My thanks to Mark Jackson for bringing the details of this hill to my attention and to Kevin McGovern and Aled Williams for their analysis of LIDAR data.
Mapping Mountains - Hill Reclassifications - Y Trichant
Teisen Priodas (SN 820 108) - Trichant addition (5th reclassification)
Survey post for Teisen Priodas
Significant Name Changes post for Teisen Priodas
Significant Height Revisions post for Teisen Priodas
Survey post for Teisen Priodas
Significant Name Changes post for Teisen Priodas
Significant Height Revisions post for Teisen Priodas
There has been an addition to the listing of the Y Trichant, these are the hills within the 300m height band of the Twmpau (thirty welsh metre prominences and upward) due to analysis of LIDAR data by Kevin McGovern and also independently by Aled Williams, and subsequently confirmed via a survey with the Trimble GeoXH 6000. With the high point of the hill previously listed in the 200m height band when the Welsh P30 hills below 500m in height were published on Geoff Crowder’s v-g.me website.
The hill had been listed with a 297m summit height positioned at SN 807 098 based on the spot height that appears on the Ordnance Survey 1:25,000 Explorer map numbers 12 and 165, whilst the Ordnance Survey 1:50,000 Landranger map number 160 gives a 298m summit spot height at the same position. This latter spot height is derived from the 978.1ft (298.1ft) height on the Ordnance Survey old Six-Inch map.
When this hill was originally listed in the Welsh P30 lists on the v-g.me website it had an accompanying note which stated ‘3 points of 300m on 1985 map may probably no longer exist (quarrying)’. The hand written Master Lists stated ‘Due to opencast workings the three points of 300c at GR 830 112 on 1985 1:50,000 map probably no longer exist’. These three points are in the vicinity of where a 984ft (299.9m) height appears on the Ordnance Survey old Six Inch map and in all likelihood signified where the summit of this hill was once positioned. Since this time the Nant Helen Openacast Mine workings which take in the northern and eastern part of the ridge known as Mynydd y Drum have destroyed the old 984ft (299.9m) summit, but in its place are two new P30 summits comprising the spoil from the mine workings, with this Hill Reclassifications post concentrating on the higher of these two artificial summits, whilst the 296.2m (converted to OSGM15) natural summit at SN 80718 09753 and listed as Mynydd y Drum still remains.
Prior to analysis of LIDAR data the ridge known as Mynydd y Drum was listed with one summit, the opencast mine has now created a further two summits which are artificial and comprise the remains of waste spoil, the summit which this Hill Reclassifications post details is now higher than the previously listed summit, resulting in new bylchau heights and positions and also drop values for these three hills, all of these will be detailed in this and two further Hill Reclassifications posts, with the name Teisen Priodas being found from local enquiry and the other two hills being Mynydd y Drum (SN 807 097) and MRF Tip (SN 828 114).
The hill is adjoined to the Fforest Fawr group with its Cardinal Hill being Fan Gyhirych (SN 880 191) and is placed in the Region of South Wales (Region C, Sub-Region C2), and it is positioned between the small communities of Abercraf (Abercrave) to the north and Y Coelbren towards the east.
The summit of the hill is situated within the Nant Helen Opencast Mine so permission to visit the high point should be sought, however it has open access land to its south-west and a public footpath marked on Ordnance Survey maps that heads in a north- south direction and at its closest point is just to the west of the summit of this hill.
The name of the hill is Teisen Priodas and its reclassification to a Trichant is due to the analysis of LIDAR data by Kevin McGovern and also independently by Aled Williams. LIDAR (Light Detection & Ranging) is highly accurate height data that is now freely available for much of England and Wales.
Kevin’s analysis of LIDAR data gives the hill the following details:
Teisen Priodas
Summit Height: 338.2m (converted to OSGM15)
Summit Grid Reference: SN 82014 10832
Bwlch Height: 244.8m (converted to OSGM15)
Bwlch Grid Reference: SN 84566 11384
Drop: 93.4m
Therefore, the 338.2m LIDAR data produced for the summit position at SN 82014 10832 and the 244.8m LIDAR data produced for the bwlch position at SN 84566 11384 is sufficient for this hill to be classified as a Trichant with 93.4m of drop and for it to be listed with a higher summit than the 296.2m (converted to OSGM15) summit of Mynydd y Drum at SN 80718 09753, with the details from the Trimble GeoXH 6000 survey being 337.9m (converted to OSGM15) summit at SN 82013 10833 and 244.6m (converted to OSGM15) bwlch at SN 84569 11383, giving this hill 93.3m of drop.
This now revises the total in the Y Trichant and the Twmpau which will be updated accordingly.
The full details for the hill are:
Cardinal Hill: Fan Gyhirych
Summit Height: 337.9m (converted to OSGM15, Trimble data)
Name: Teisen Priodas
OS 1:50,000 map: 160
Summit Grid Reference: SN 82013 10833
Drop: 93.3m (converted to OSGM15, Trimble data)
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| Teisen Priodas (SN 820 108) a new addition to the Y Trichant list |
My thanks to Mark Jackson for bringing the details of this hill to my attention and to Kevin McGovern and Aled Williams for their analysis of LIDAR data.
Mapping Mountains - Hill Reclassifications - Y Trichant
Penmaen Mawr (SH 702 757) - Sub-Trichant addition (4th reclassification)
Survey post for Penmaen Mawr
THIS HILL HAS SUBSEQUENTLY BEEN RECLASSIFIED FROM A SUB-TRICHANT TO A TRICHANT
The following details have been superseded by analysis of LIDAR data by Aled Williams with the result that this hill has been reclassified from a Sub-Trichant to a Trichant as LIDAR data gives the hill 31.3m of drop. The Y Trichant are the Welsh P30 hills in the 300m height band of the Twmpau.
The below is the Hill Reclassifications post prior to LIDAR data analysis:
There has been a promotion to the listing of Twmpau (thirty welsh metre prominences and upward) hills due to a recent survey with the Trimble GeoXH 6000. The hill is now listed in the Sub-List adjoined to the 300m height band of Twmpau hills and is situated in the northern Carneddau in north-west Wales.
The hill was not classified prior to the survey with the Trimble as the majority of the summit has been quarried and there is a lack of uppermost contour lines on current Ordnance Survey maps. But at one stage it was a part of a relatively substantial hill that had a prominence in excess of 100m and a 1,550ft (472m) summit map height on the Ordnance Survey Popular and New Popular One-Inch maps, with this height also appearing on the Ordnance Survey Six-Inch map published in 1888, and therefore it would have met the criteria specified for inclusion to the Humps and the Y Pedwarau listings.
Because of this the hill did not appear in the Sub-List which accompanied the original Welsh P30 listings on Geoff Crowder’s v-g.me website as the Sub-List only included hills whose map details showed that when surveyed they may stand a chance of qualification to the main P30 list, with the title of the Sub-List being ‘Hills to be surveyed.’ And as this hill only has an uppermost 350m contour line in the vicinity of its summit area and also bwlch, map detail intimated that there was insufficient drop for inclusion to this Sub-List. However, since first publication this Sub-List has been standardised and now includes all hills that have a minimum of 20m of drop and below 30m of drop.
The hill is situated to the south of the A 55 and is positioned between the towns of Llanfairfechan to its west and Penmaenmawr to its east, with the latter taking its name from the hill. The quarrying of this hill has now left two distinct summits, the higher western summit and the lower easterly summit which this post details.
The hill can be easily accessed from a minor road to the south of the summit that reaches over 260m in height, a public footpath heads north from just below the high point of this minor road and joins a bridlewayed track that contours around the southern slopes of the upper section of the hill. A large section of the land above the bridleway is open access and the summit Penmaen Mawr is close to this.
The survey with the Trimble GeoXH 6000 resulted in a 384.9m (converted to OSGM15) summit height and a 355.1m (converted to OSGM15) bwlch height, giving this hill 29.8m of drop and therefore it qualifies as a 300m Sub-Twmpau.
The full details for the hill are:
Cardinal Hill: Carnedd Llywelyn
Summit Height: 384.9m (converted to OSGM15)
Name: Penmaen Mawr
OS 1:50,000 map: 115
Summit Grid Reference: SH 70200 75727
Drop: 29.8m (converted to OSGM15)
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| Penmaen Mawr (SH 702 757) now classified as a 300m Sub-Twmpau |
Myrddyn Phillips (August 2016)
Moel y Gôd (SJ 072 168) - 300m Sub-Twmpau reclassified to 300m Twmpau (3rd reclassification)
Survey post for Moel y Gôd
There has been a reclassification to the 300m Twmpau (thirty welsh metre prominences and upward) hill list with its confirmation as a P30 instigated by a survey with the Trimble. The hill is situated between Llanwddyn to its west, Dolanog to its south, Llanfyllin to its east and Pen-y-bont-fawr to its north, and is positioned in the central part of the Y Berwyn.
The hill is named Moel y Gôd and the first time it ever appeared in a hill list was in 2003 when the original Welsh P30 hills under 500m in height were published on Geoff Crowder’s v-g.me website. It was then listed in the Sub-List which was named ‘Hills to Survey’. The reason for this was that Moel y Gôd was only given a 308m summit spot height on current maps, and meant that its qualification to the main P30 list was dependent upon bwlch contour interpolation. As the use of interpolation did not form part of this list the hill was listed in the ‘Hills to Survey’ Sub-List. When this list was first published on Geoff’s website it did not include a drop value for each hill, although the qualification for the main list and the Sub-List was based on drop, these values were added to the list at a later date.
When these drop values were added I also decided to include hills in the Main P30 Twmpau list through interpolation of map contours, although some of these details were passed onto Geoff, the great majority were not. When these figures were added to the list I gave Moel y Gôd c 35m of drop and promoted it into the ranks of P30 hills. This drop value was estimated from its 308m summit spot height and an estimated bwlch height of c 273m based on the 1:25,000 map bwlch contouring between 270m – 280m. Even though the hill had been promoted in my list the details were never made public, so it was now time to have it Trimbled and to confirm its status via the Mapping Mountains site.
The hill can be accessed from where a public footpath contours round its northern flank; however the summit is not situated on open access land so permission to visit should be sought. There is sufficient parking for one or two vehicles near the intersection between the B 4393 and the B 4395 which is only a short distance from the gate giving access on to the footpath.
The survey with the Trimble GeoXH 6000 resulted in a 307.6m (converted to OSGM15) summit height and a 270.6m (converted to OSGM15) bwlch height; these values give this hill 37.0m of drop and confirm its status as a P30 Twmpau.
The full details for the hill are:
Cardinal Hill: Rhialgwm
Summit Height: 307.6m (converted to OSGM15)
Name: Moel y Gôd
OS 1:50,000 map: 125
Summit Grid Reference: SJ 07248 16808
Drop: 37.0m (converted to OSGM15)
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| Moel y Gôd (SJ 07248 16808) now confirmed as a 300m Twmpau |
For details on the survey that confirmed this hill's 300m Twmpau status please click {here}
Myrddyn Phillips (May 2016)
Mapping Mountains - Hill Reclassifications - Y Trichant
Pen y Gaer (SO 139 976) - 200m Twmpau reclassified to 300m Twmpau (2nd reclassification)
Survey post for Pen y Gaer
There has been a new addition to the 300m Twmpau list due to a survey with the Trimble GeoXH 6000. The evidence for the promotion of this hill is marginal, but until more accurate information is at hand the hill has been reclassified from the ranks of the 200m Twmpau to that of the 300m Twmpau list.
The raw processed survey result is 300.002m converted to OSGM15
The margin of uncertainty for the height in relation to the position of the Trimble on the summit is 0.05m.
The precision of the equipment is +/- 0.15m.
The accuracy of the equipment is 0.1m.
The name of the hill is Pen y Gaer (SO 139 976) and it is situated in the Carnedd Wen range of hills and is positioned between the small communities of Betws Cedewain and Pentrellifior.
The full details for the hill are:
Cardinal Hill: Carnedd Wen
Summit Height: 300.0m (converted to OSGM15)
Name: Pen y Gaer
OS 1:50,000 map: 136
Summit Grid Reference: SO 13997 97677
Bwlch Height: 214.8m (converted to OSGM15)
Bwlch Grid Reference: SO 13170 99222
Drop: 85.2m
Bwlch Grid Reference: SO 13170 99222
Drop: 85.2m
.jpg) |
| Pen y Gaer (SO 139 976) the new 300m Twmpau |
For details on the survey that reclassified this hill to 300m Twmpau status please click {here}
Myrddyn Phillips (January 2015)
Mapping Mountains - Hill Reclassifications - Y Trichant
Mynydd Derw Llwydion (SO 904 900) - 300m Sub-Twmpau reclassified to 300m Twmpau (1st reclassification)
1st Survey post for Mynydd Derw Llwydion
2nd Survey post for Mynydd Derw Llwydion
Significant Height Revisions post for Mynydd Derw Llwydion
Summit Relocations post for Mynydd Derw Llwydion
There is an addition to the 300m Twmpau list due to a survey with the Trimble GeoXH 6000, subsequent LIDAR analysis and a further survey with the Trimble, all of which were conducted by Myrddyn Phillips.
The hill was previously listed as a 300m Sub-Twmpau with 29m of drop, based on the 387m summit spot height and the 358m bwlch spot height that appear on the Ordnance Survey 1:25,000 Explorer map, and it is situated in the Pumlumon range and positioned between Llyn Clywedog and Penffordd-las (Staylittle).
The Trimble survey gave the hill sneaking in to P30 status with 14 millimetres to spare! This margin is within the uncertainty applied to the equipment and its positioning at the summit and the bwlch. However, reclassifications are taking place in the listings I have compiled and those jointly co-authored with Aled Williams, from best available evidence on any given day and as the data produced by the Trimble is more accurate that spot heights produced by photogrametry, the Trimble result was taken for the recalssification of this hill.
However, since this survey LIDAR is now available and the subsequent height and position derived from LIDAR prompted a further survey with the Trimble GeoXH 6000.
The full details for the hill are:
Group: Pumlumon
Name: Mynydd Derw Llwydion
OS 1:50,000 map: 136
OS 1:50,000 map: 136
Summit Height: 389.3m (converted to OSGM15, Trimble GeoXH 6000)
Summit Grid Reference: SN 90460 90041
Bwlch Height: 358.1m (converted to OSGM15, Trimble GeoXH 6000)
Bwlch Grid Reference: SN 90391 90264
Drop: 31.3m
Bwlch Grid Reference: SN 90391 90264
Drop: 31.3m
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| LIDAR image of Mynydd Derw Llwydion (SN 904 900) |
For details on the survey that reclassified this hill to 300m Twmpau status please click {here}
For details on the second Trimble GeoXH 6000 survey of this hill
For details on the second Trimble GeoXH 6000 survey of this hill
Myrddyn Phillips (April 2014)
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