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
Banc (SN 723 729) – Sub-Trichant reclassified to Trichant (70th 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 initially confirmed by Joe Nuttall who produced a summit analysis programme using LIDAR, and then by LIDAR analysis initially conducted by Jim Bloomer and subsequently by Myrddyn Phillips.
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| LIDAR image of Banc (SN 723 729) |
The criteria for the list that this reclassification 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.
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| Y Trichant - The 300m Hills of Wales by Myrddyn Phillips |
The name the hill is now listed by is Banc and this was derived from the Tithe map, and it is adjoined to the Elenydd group of hills, which are situated in the western part of Mid and West Wales (Region B, Sub-Region B2), and it is positioned with minor roads to its north and south and has the B4340 road to its west and the B4343 road to its east, and has the village of Pont-rhyd-y-groes towards the east 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 included in the Hills to be surveyed sub list, as it was considered not to meet the criteria then used for the accompanying 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 with an estimated c 30m of drop, based on the 316m summit spot height and a c 286m bwlch height, with the latter based on interpolation of 10m contouring between 280m – 290m that appear on the Ordnance Survey 1:25,000 Explorer map.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
The details for this hill were later re-assessed and the interpolated bwlch height amended to c 287m, and when coupled with this hill’s 316m summit height these values gave this hill an estimated c 29m 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.
Therefore, the reclassification of this hill from Sub-Trichant status is due to LIDAR analysis, resulting in a 316.0m summit height and a 285.1m bwlch height, with these values giving this hill 30.9m of drop, which is sufficient for it to be classified as a Trichant.
The full details for the hill are:
Group: Elenydd
Name: Banc
OS 1:50,000 map: 135, 147
Summit Height: 316.0m (LIDAR)
Summit Grid Reference: SN 72380 72986 (LIDAR)
Bwlch Height: 285.1m (LIDAR)
Bwlch Grid Reference: SN 72097 73104 (LIDAR)
Drop: 30.9m (LIDAR)
Myrddyn Phillips (November 2020)
Mapping Mountains - Hill Reclassifications - Y Trichant
Coed y Fedw (SJ 201 613) – Sub-Trichant addition (69th 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 derived from detail on contemporary maps produced from Ordnance Survey data.
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.
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| Y Trichant - The 300m Hills of Wales by Myrddyn Phillips |
The name the hill is listed by is Coed y Fedw, and it is adjoined to the Moel y Gamelin 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 A494 road to its north-west and minor roads to its south and east, and has the village of Gwernymynydd 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 not included in the Hills to be surveyed sub list that accompanied the main P30 list, as it was considered not to meet the criteria then used for this sub category.
After the P30 lists were standardised, and interpolated heights and drop values also included, and the lists updated, this hill was listed with an estimated c 24m of drop based on an estimated c 317m summit height and an estimated c 293m bwlch height based on interpolated detail from the Ordnance Survey 1:25,000 Explorer map.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
Since publication of these P30 lists on Geoff Crowder’s v-g.me website there have been a number of Ordnance Survey maps made available online, some of these are historic such as the series of Six-Inch maps on the National Library of Scotland website, whilst others are current and digitally updated such as the mapping on the WalkLakes website, and it is this mapping that gives this hill a 318m summit spot height.
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| Extract from the WalkLakes website |
The details for this hill were also re-assessed against the mapping on the OS Maps website. This is the replacement for OS Get-a-map and until recent times had contours at 5m intervals which were proving consistently more accurate compared to the 5m contours that sometimes appear on the Ordnance Survey 1:25,000 Explorer map and used to appear on the online Vector Map Local. This resulted in its bwlch height being listed as c 294m based on interpolation of 5m contouring between 290m – 295m.
Therefore, the addition of this hill to Sub-Trichant status is due to detail on contemporary maps produced from Ordnance Survey data, resulting in a 318m summit height and a c 294m bwlch height, with these values giving this hill c 24m of drop, which is sufficient for it to be classified as a Sub-Trichant.
The full details for the hill are:
Group: Moel y Gamelin
Name: Coed y Fedw
OS 1:50,000 map: 117
Summit Height: 318m (spot height)
Summit Grid Reference: SJ 20180 61372 (spot height)
Bwlch Height: c 294m (interpolation)
Bwlch Grid Reference: SJ 20367 61266 (interpolation)
Drop: c 24m (spot height summit and interpolated bwlch)
Myrddyn Phillips (October 2020)
Mapping Mountains - Hill Reclassifications - Y Trichant
Cefn Penarth (SN 924 853) – Sub-Trichant reclassified to Trichant (68th 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 initially confirmed by Joe Nuttall who produced a summit analysis programme using LIDAR, and then by LIDAR analysis initially conducted by Jim Bloomer and subsequently by Myrddyn Phillips, with the hill previously surveyed with the Trimble GeoXH 6000.
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| Cefn Penarth (SN 924 853) |
The criteria for the list that this reclassification 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.
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| Y Trichant - The 300m Hills of Wales by Myrddyn Phillips |
The name the hill is now listed by is Cefn Penarth and this was derived from local enquiry, and it is adjoined to the Pumlumon group of hills, which are situated in the north-western part of Mid and West Wales (Region B, Sub-Region B2), and it is positioned between the river valleys of the Afon Clewedog to its north and the Afon Hafren (River Severn) to its south, and has a minor road running the length of its ridge and the B4518 road to its north-east, and has the town of Llanidloes towards the east south-east.
When the original 300m height band of Welsh P30 hills was published on Geoff Crowder’s v-g.me website this hill was included in the Hills to be surveyed sub list, as it was considered not to meet the criteria then used for the accompanying 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 with 29m of drop based on the 317m summit spot height and the 288m bwlch spot height that appear on the Ordnance Survey 1:25,000 Explorer map.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
As the listed drop was close to the 30m minimum drop required for Trichant status this hill was prioritised for a GNSS survey, and this took place on the 20th April 2014, resulting in 29.8m of drop. However, since this hill was Trimbled, LIDAR is now available and the summit analysis undertaken by Joe Nuttall and LIDAR analysis conducted by Jim Bloomer prompted me to compare the Trimble result against the LIDAR. The Trimble result is 0.07m lower for the summit compared to LIDAR, but with an approximate 16 metre difference in summit position and a 7 metre difference in bwlch position, the LIDAR result is being prioritised.
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| LIDAR image of Cefn Penarth |
The LIDAR (Light Detection & Ranging) technique produced highly accurate height data that is now freely available for much of England and Wales and is revolutionising hill classification.
Therefore, the reclassification of this hill from Sub-Trichant status is due to LIDAR analysis, resulting in a 318.9m summit height and a 288.9m bwlch height, with these values giving this hill 30.0m of drop, which is sufficient for it to be classified as a Trichant.
The full details for the hill are:
Group: Pumlumon
Name: Cefn Penarth
OS 1:50,000 map: 136
Summit Height: 318.9m (LIDAR)
Summit Grid Reference: SN 92419 85333 (LIDAR)
Bwlch Height: 288.9m (LIDAR)
Bwlch Grid Reference: SN 92025 85612 (LIDAR)
Drop: 30.0m (LIDAR)
Myrddyn Phillips (October 2020)
Mapping Mountains - Hill Reclassifications - Y Trichant
Hafod LlÅ·n (SN 625 700) – Sub-Trichant reclassified to Trichant (67th reclassification)
Survey Post for Hafod LlÅ·n
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 confirmed by LIDAR analysis and a subsequent Trimble GeoXH 6000 survey.
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| LIDAR image of Hafod LlÅ·n (SN 625 700) |
This was initiated by Joe Nuttall who produced a summit analysis programme that used LIDAR with an alternative height map (DEM) allowing identification of summits and cols and thereby drops. The resulting spreadsheet that Joe produced contains over 29,600 hills.
This spreadsheet is being evaluated by a number of people, and for this particular hill it was Jim Bloomer who initially assessed the data on the spreadsheet produced for this hill against that produced via LIDAR.
Myrddyn Phillips then evaluated the details for this hill via LIDAR analysis and confirmed its height and drop and hence its reclassification to Trichant status.
The criteria for the list that this reclassification 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 now listed by is Hafod LlÅ·n and this was derived from the Tithe map and local enquiry, and it is adjoined to the Hafod Ithel group of hills, which are situated in the western part of Mid and West Wales (Region B, Sub-Region B3), and it is encircled by minor roads and farther afield it has the B4576 road to its west and the A485 road to its east, and has the village of Lledrod towards the east.
When the original 300m height band of Welsh P30 hills was published on Geoff Crowder’s v-g.me website this hill was included in the Hills to be surveyed sub list, as it was considered not to meet the criteria then used for the accompanying 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 with an estimated c 27m of drop based on the 330m summit spot height and an estimated c 303m bwlch height, with the latter based on interpolation of 10m contouring between 300m – 310m that appear on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
However, it was not until LIDAR became available that the details for this hill could be accurately re-assessed. The LIDAR (Light Detection & Ranging) technique produced highly accurate height data that is now freely available for much of England and Wales.
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| LIDAR summit image for Hafod LlÅ·n |
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| LIDAR bwlch image for Hafod LlÅ·n |
The result produced by LIDAR analysis gives this hill a 330.7m summit height, and as the summit has now been surveyed with the Trimble GeoXH 6000 it is this result that is being prioritised for listing purposes.
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| The Trimble GeoXH 6000 gathering data at the summit of Hafod LlÅ·n |
Therefore, the reclassification of this hill from Sub-Trichant status is due to LIDAR analysis and a subsequent Trimble GeoXH 6000 survey, resulting in a 330.6m summit height and a 300.0m bwlch height, with these values giving this hill 30.6m of drop, which is sufficient for it to be classified as a Trichant.
The full details for the hill are:
Group: Hafod Ithel
Name: Hafod LlÅ·n
OS 1:50,000 map: 135
Summit Height: 330.6m (converted to OSGM15, Trimble GeoXH 6000)
Summit Grid Reference: SN 62592 70023 (Trimble GeoXH 6000)
Bwlch Height: 300.0m (LIDAR)
Bwlch Grid Reference: SN 62234 69672 & SN 62235 69675 (LIDAR)
Drop: 30.6m (Trimble GeoXH 6000 summit and LIDAR bwlch)
Myrddyn Phillips (September 2020)
Mapping Mountains - Hill Reclassifications - Y Trichant
Gyrn (SJ 165 585) – Sub-Trichant addition (66th 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 derived from detail on contemporary maps produced from Ordnance Survey data.
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.
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| Y Trichant - The 300m Hills of Wales by Myrddyn Phillips |
The name the hill is listed by is Gyrn, and it is adjoined to the Bryniau Clwyd 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 A494 road to its west, south and east, and has the town of Rhuthun (Ruthin) towards the 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 was considered not to 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 26m of drop, based on the 384m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and the 358m bwlch spot height that appeared on the Ordnance Survey Vector Map Local hosted on the Geograph website and which was entitled the Interactive Coverage Map.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
Therefore, the addition of this hill to Sub-Trichant status is due to detail on contemporary maps produced from Ordnance Survey data, resulting in a 384m summit height and a 358m bwlch height, with these values giving this hill 26m of drop, which is sufficient for it to be classified as a Sub-Trichant.
The full details for the hill are:
Group: Bryniau Clwyd
Name: Gyrn
OS 1:50,000 map: 116
Summit Height: 384m (spot height)
Summit Grid Reference: SJ 16519 58531 (spot height)
Bwlch Height: 358m (spot height)
Bwlch Grid Reference: SJ 16719 58839 (spot height)
Drop: 26m (spot height summit and bwlch)
Myrddyn Phillips (September 2020)
Mapping Mountains - Hill Reclassifications - Y Trichant
Cefn Twrch (SN 899 317) – Sub-Trichant reclassified to Trichant (65th reclassification)
Summit Relocations post for Cefn Twrch
There has been confirmation of 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 confirmed by LIDAR analysis.
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| LIDAR image of Cefn Twrch (SN 899 317) |
This was initiated by Joe Nuttall who produced a summit analysis programme that used LIDAR with an alternative height map (DEM) allowing identification of summits and cols and thereby drops. The resulting spreadsheet that Joe produced contains over 29600 hills.
This spreadsheet is being evaluated by DoBIH Editors and others, and for this particular hill it was Chris Crocker who initially assessed its height and that of its adjacent peak via LIDAR analysis.
Myrddyn Phillips then evaluated this hill’s details via LIDAR analysis and confirmed its height and drop and hence the confirmation of its reclassification to Trichant status.
The criteria for the list that this reclassification 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.
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| Y Trichant - The 300m Hills of Wales by Myrddyn Phillips |
The name the hill is listed by is Cefn Twrch, and it is adjoined to the Mynydd Epynt group of hills, which are situated in the south-eastern part of Mid and West Wales (Region B, Sub-Region B2), and it is positioned with minor roads to its east, north and west and the A40 road to its south, and has the hamlet of Pentre-bach towards the north-east.
When the original 300m height band of Welsh P30 hills was published on Geoff Crowder’s v-g.me website this hill was included in the Hills to be surveyed sub list, as it was considered not to meet the criteria then used for the accompanying main P30 list, and it was listed as a 378m map heighted twin summit with the prioritised summit positioned at SN 898 321 and its twin map heighted summit positioned at SN 904 307.
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| 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 and it was listed with an estimated c 32m of drop based on the twin 378m summit spot heights that appear on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map and an estimated c 346m bwlch height based on interpolation of 10m contouring between 340m – 350m.
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| Extract from the Ordnance Survey 1:50,000 Landranger map |
The details for this hill were re-assessed when the Ordnance Survey Vector Map Local hosted on the Geograph website and which is entitled the Interactive Coverage Map became available online. This mapping had many spot heights not shown on other publicly available Ordnance Survey maps and for this hill it showed a 342m bwlch spot height and when coupled with the 378m summit spot height it gave this hill 36m of drop.
However, it was not until LIDAR became available that the details for these two summits 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 LIDAR result for each summit appears below:
Cefn Twrch (previous prioritised twin summit) 379.4m at SN 89923 31751
Cefn Twrch (previous non-prioritised twin summit) 377.8m at SN 90489 30697
The prioritised summit is confirmed the higher, although its position has moved from where the 378m spot height appears on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer maps, and its drop confirmed sufficient for it to be classified as a Trichant, with the drop of the old twin summit confirmed as 11.6m which is insufficient for it to be classified as a Sub-Trichant.
Therefore, the confirmation of the reclassification of this hill to Trichant status is due to LIDAR analysis, resulting in a 379.4m summit height and a 347.2m bwlch height, with these values giving this hill 32.2m of drop, which is sufficient for it to be classified as a Trichant.
The full details for the hill are:
Group: Mynydd Epynt
Name: Cefn Twrch
OS 1:50,000 map: 160
Summit Height: 379.4m (LIDAR)
Summit Grid Reference: SN 89923 31751 (LIDAR)
Bwlch Height: 347.2m (LIDAR)
Bwlch Grid Reference: SN 89591 32567 (LIDAR)
Drop: 32.2m (LIDAR)
Mapping Mountains - Hill Reclassifications - Y Trichant
Mynydd Bach (SN 992 359) – Trichant reclassified to Sub-Trichant (64th 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 confirmed by LIDAR analysis.
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| LIDAR image of Mynydd Bach (SN 992 359) |
This spreadsheet is being evaluated by DoBIH Editors and others, and for this particular hill it was Jim Bloomer who initially assessed its height and that of its adjacent peak via LIDAR analysis.
Myrddyn Phillips then evaluated this hill’s details via LIDAR analysis and confirmed its height and hence its reclassification to Sub-Trichant status.
The criteria for the list that this reclassification 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.
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| Y Trichant - The 300m Hills of Wales by Myrddyn Phillips |
The name the hill is listed by is Mynydd Bach, and it is adjoined to the Mynydd Epynt group of hills, which are situated in the south-eastern part of Mid and West Wales (Region B, Sub-Region B2), and it is positioned with minor roads to its east, north and west and farther afield it has the A40 road to its south and the B4520 road to its east, and has the hamlet of Merthyr Cynog towards the north north-west.
When the original 300m height band of Welsh P30 hills was published on Geoff Crowder’s v-g.me website this hill was listed as a 387m map heighted twin summit with its adjacent hill positioned at SN 992 359.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
However, it was not until LIDAR became available that the details for these two hills 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 LIDAR result for each hill appears below:
Lan 385.9m summit at SN 98815 36321
Mynydd Bach 385.3m summit at SN 99215 35955
As Lan is higher than Mynydd Bach it is retained as the Trichant, whilst the drop is sufficient for Mynydd Bach to be classified as a Sub-Trichant.
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| LIDAR image of Lan (SN 988 363) and Mynydd Bach (SN 992 359) |
Therefore, the reclassification of this hill to Sub-Trichant status is due to LIDAR analysis, resulting in a 385.3m summit height and a 362.9m bwlch height, with these values giving this hill 22.3m of drop, which is sufficient for it to be classified as a Sub-Trichant.
The full details for the hill are:
Group: Mynydd Epynt
Name: Mynydd Bach
OS 1:50,000 map: 160
Summit Height: 385.3m (LIDAR)
Summit Grid Reference: SN 99215 35955 (LIDAR)
Bwlch Height: 362.9m (LIDAR)
Bwlch Grid Reference: SN 98996 36093 (LIDAR)
Drop: 22.3m (LIDAR)
Myrddyn Phillips (September 2020)
Pt. 346m (SH 987 631) – Sub-Trichant addition (63rd 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 derived from detail on contemporary maps produced from Ordnance Survey data.
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.
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| Y Trichant - The 300m Hills of Wales by Myrddyn Phillips |
The hill is being listed by the point (Pt. 346m) notation as an appropriate name for it either through local enquiry and / or historic research has not been found by the author, and it is adjoined to the Mynydd Hiraethog group of hills which are situated in the north-eastern part of North Wales (Region A, Sub-Region A2), and it is enclosed by minor roads with the B5435 road to its south-west and the A543 road to its north, and has the town of Dinbych (Denbigh) towards the east 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 not included in the Hills to be surveyed sub list that accompanied the main P30 list, as it was considered not to 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 against the Ordnance Survey Vector Map Local hosted on the Geograph website and which was entitled the Interactive Coverage Map. This mapping had many spot heights not shown on other publicly available Ordnance Survey maps and for this hill it showed a 346m summit spot height and when coupled with the estimated c 321m bwlch height which was based on interpolation of 10m contouring between 320m – 330m that appear on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map, it gave this hill an estimated c 25m of drop.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
The details for this hill were re-assessed when the OS Maps website became available online. This is the replacement for OS Get-a-map and has contours at 5m intervals which are proving consistently more accurate compared to the 5m contours that sometimes appear on Ordnance Survey 1:25,000 Explorer maps and used to appear on the online Vector Map Local. This re-assessment resulted in the estimated bwlch height for this hill remaining the same at c 321m, with this based on interpolation of 5m contouring between 320m – 325m.
Therefore, the confirmation of the addition of this hill to Sub-Trichant status is due to detail derived from contemporary maps produced from Ordnance Survey data, resulting in a 346m summit height and an estimated c 321m bwlch height, with these values giving this hill c 25m 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: Pt. 346m
OS 1:50,000 map: 116
Summit Height: 346m (spot height)
Summit Grid Reference: SH 98793 63125 (spot height)
Bwlch Height: c 321m (interpolation)
Bwlch Grid Reference: SH 99042 63253 (interpolation)
Drop: c 25m (spot height summit and interpolated bwlch)
Myrddyn Phillips (September 2020)
Cefn Uchaf (SJ 012 461) – Sub-Trichant addition (62nd reclassification)
Significant Name Changes post for Cefn Uchaf
Significant Height Revisions post for Cefn Uchaf
Summit Relocations post for Cefn Uchaf
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 Cefn Uchaf (SJ 012 461) |
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 Cefn Uchaf and this was derived from the Tithe map, 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 B5105 road to its north, the A5 road to its south and the A494 road to its east, and has the town of Corwen towards the east 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 that accompanied the main P30 list, as it was considered not to 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 and it was listed with 2om of drop, based on the 337m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and the 317m bwlch spot height that appeared on the Ordnance Survey Vector Map Local hosted on the Geograph website and which is entitled the Interactive Coverage Map.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
However, it was not until LIDAR became available that the details for this hill could be accurately re-assessed. The LIDAR (Light Detection & Ranging) technique produced highly accurate height data that is now freely available for much of England and Wales.
Therefore, the confirmation of the addition of this hill to Sub-Trichant status is due to LIDAR analysis, resulting in a 340.0m summit height and a 319.1m 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: Mynydd Hiraethog
Name: Cefn Uchaf
OS 1:50,000 map: 116
Summit Height: 340.0m (LIDAR)
Summit Grid Reference: SJ 01294 46112 (LIDAR)
Bwlch Height: 319.1m (LIDAR)
Bwlch Grid Reference: SJ 00949 46115 (LIDAR)
Drop: 20.9m (LIDAR)
Mapping Mountains - Hill Reclassifications - Y Trichant
Ffridd Bryn Helen (SH 967 518) – Sub-Trichant addition (61st 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 Ffridd Bryn Helen (SH 967 518) |
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 Ffridd Bryn Helen, 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 B4501 road to its west and the B5105 road to its south-east, and has the village of Llanfihangel Glyn Myfyr towards the 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 that accompanied the main P30 list, as it was considered not to 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 and it was listed with c 23m of drop, based on the 388m summit spot height and an estimated c 365m bwlch height, based on interpolation of bwlch contouring between 360m – 370m that appears on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
However, it was not until LIDAR became available that the details for this hill could be accurately re-assessed. The LIDAR (Light Detection & Ranging) technique produced highly accurate height data that is now freely available for much of England and Wales.
Therefore, the confirmation of the addition of this hill to Sub-Trichant status is due to LIDAR analysis, resulting in a 387.5m summit height and a 363.9m bwlch height, with these values giving this hill 23.6m 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: Ffridd Bryn Helen
OS 1:50,000 map: 116
Summit Height: 387.5m (LIDAR)
Summit Grid Reference: SH 96717 51883 (LIDAR)
Bwlch Height: 363.9m (LIDAR)
Bwlch Grid Reference: SH 96841 51697 (LIDAR)
Drop: 23.6m (LIDAR)
Myrddyn Phillips (July 2020)
Ffridd Uchaf (SH 993 500) – Sub-Trichant addition (60th reclassification)
Significant Name Changes post for Ffridd Uchaf
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 Ffridd Uchaf (SH 993 500) |
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 Ffridd Uchaf and this was derived from the Tithe map, 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 B4501 road to its west and the B5105 road to its south, and has the village of Llanfihangel Glyn Myfyr 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 was considered not to 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 and it was listed with 24m of drop, based on the 375m summit spot height that appears on the Ordnance Survey 1:50,000 Landranger map and the 351m bwlch spot height that appeared at SH 99666 50565 on the Ordnance Survey Vector Map Local hosted on the Geograph website and which is entitled the Interactive Coverage Map.
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| Extract from the Ordnance Survey 1:50,000 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.
Therefore, the confirmation of the addition of this hill to Sub-Trichant status is due to LIDAR analysis, resulting in a 376.4m summit height and a 350.5m bwlch height, with these values giving this hill 25.9m 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: Ffridd Uchaf
OS 1:50,000 map: 116
Summit Height: 376.4m (LIDAR)
Summit Grid Reference: SH 99378 50074 (LIDAR)
Bwlch Height: 350.5m (LIDAR)
Bwlch Grid Reference: SH 99671 50547 (LIDAR)
Drop: 25.9m (LIDAR)
Myrddyn Phillips (July 2020)
Derwydd Bach (SJ 017 503) – Sub-Trichant addition (59th 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 derived from detail on contemporary maps produced from Ordnance Survey data.
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 Derwydd Bach 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 B5105 road to its south, and has the village of Clawddnewydd towards the east 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 not included in the Hills to be surveyed sub list that accompanied the main P30 list, as it was considered not to 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 and it was listed with an estimated c 27m of drop, based on the 399m summit spot height and an estimated bwlch height of c 372m based on interpolation of 10m contouring between 370m – 380m that appear on the Ordnance Survey 1:25,000 Explorer map.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
The details for this hill were re-assessed when the OS Maps website became available online. This is the replacement for OS Get-a-map and has contours at 5m intervals which are proving consistently more accurate compared to the 5m contours that sometimes appear on Ordnance Survey 1:25,000 Explorer maps and used to appear on the online Vector Map Local. This re-assessment resulted in the estimated bwlch height for this hill remaining the same at c 372m, with this based on interpolation of 5m contouring between 370m – 375m.
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| Extract from the OS Maps website |
Therefore, the confirmation of the addition of this hill to Sub-Trichant status is due to detail derived from contemporary maps produced from Ordnance Survey data, resulting in a 399m summit height and an estimated c 372m bwlch height, with these values giving this hill c 27m 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: Derwydd Bach
OS 1:50,000 map: 116
Summit Height: 399m (spot height)
Summit Grid Reference: SJ 01776 50305 (spot height)
Bwlch Height: c 372m (interpolation)
Bwlch Grid Reference: SJ 01658 50623 (interpolation)
Drop: c 27m (spot height summit and interpolated bwlch)
Myrddyn Phillips (July 2020)
Pt. 335.0m (SJ 044 499) – Sub-Trichant addition (58th 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 summit image of Pt. 335.0m (SJ 044 499) |
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. 335.0m) notation as an appropriate name for it either through local enquiry and / or historic research has not been found by the author, and it is adjoined to the Mynydd 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 B5105 road to its north, the A5 road to its south-west and the A494 road to its east, and has the village of Clawddnewydd towards the north-east and the town of Corwen towards the south 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 that accompanied the main P30 list, as it was considered not to 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 and it was listed with an estimated c 22m of drop, based on the 335m summit spot height and an estimated bwlch height of c 313m based on interpolation of 10m contouring between 310m – 320m that appear on the Ordnance Survey 1:25,000 Explorer map.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
However, it was not until LIDAR became available that the details for this hill could be accurately re-assessed. The LIDAR (Light Detection & Ranging) technique produced highly accurate height data that is now freely available for much of England and Wales.
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| LIDAR bwlch image for Pt. 335m |
Therefore, the confirmation of the addition of this hill to Sub-Trichant status is due to LIDAR analysis, resulting in a 335.0m summit height and a 309.7m bwlch height, with these values giving this hill 25.4m 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: Pt. 335.0m
OS 1:50,000 map: 116
Summit Height: 335.0m (LIDAR)
Summit Grid Reference: SJ 04495 49942 (LIDAR)
Bwlch Height: 309.7m (LIDAR)
Bwlch Grid Reference: SJ 04991 50477 (LIDAR)
Drop: 25.4m (LIDAR)
Myrddyn Phillips (July 2020)
Pt. 369.4m (SJ 047 509) – Sub-Trichant addition (57th reclassification)
There has been confirmation of an addition to the list of Y Trichant – The 300m Hills of Wales, with the summit height and its location confirmed by LIDAR analysis conducted by Myrddyn Phillips, and the bwlch height and its location, the drop and status of the hill derived from detail on contemporary maps produced from Ordnance Survey data.
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| LIDAR image of Pt. 369.4m (SJ 047 509) |
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. 369.4m) notation as an appropriate name for it either through local enquiry and / or historic research has not been found by the author, and it is adjoined to the Mynydd 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 B5105 road to its north and minor roads to it immediate west and south-east, with the A494 road further to its south-east, and has the village of Clawddnewydd towards the east 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 not included in the Hills to be surveyed sub list that accompanied the main P30 list, as it was considered not to 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 and it was listed with an estimated c 29m of drop, based on an estimated c 370m summit height and the 341m bwlch spot height that appears on the Ordnance Survey 1:25,000 Explorer map.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
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 confirmation of the addition of this hill to Sub-Trichant status is due to LIDAR analysis which only covers the summit area and detail derived from contemporary maps produced from Ordnance Survey data, resulting in a 369.35m summit height and a 341m bwlch height, with these values giving this hill 28m 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: Pt. 369.4m
OS 1:50,000 map: 116
Summit Height: 369.4m (LIDAR)
Summit Grid Reference: SJ 04708 50996 (LIDAR)
Bwlch Height: 341m (spot height)
Bwlch Grid Reference: SJ 04933 51669 (spot height)
Drop: 28m (LIDAR summit and spot height bwlch)
Myrddyn Phillips (June 2020)
Foel (SJ 074 521) – Sub-Trichant addition (56th reclassification)
Significant Name Changes post for Foel
There has been confirmation of an addition to the list of Y Trichant – The 300m Hills of Wales, with the summit height and its location confirmed by LIDAR analysis conducted by Myrddyn Phillips, and the bwlch height and its location, the drop and status of the hill derived from detail on contemporary maps produced from Ordnance Survey data.
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| LIDAR summit image of Foel (SJ 074 521) |
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 Foel, 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 B5105 road to its north and minor roads to it immediate west and south-east, with the A494 road further to its south-east, and has the village of Clawddnewydd towards the east 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 not included in the Hills to be surveyed sub list that accompanied the main P30 list, as it was considered not to 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 and it was listed with an estimated c 21m of drop, based on the 325m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map, and an estimated bwlch height of c 304m based on interpolation of 10m contouring between 300m – 310m on contemporary Ordnance Survey maps.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
The details for this hill were re-assessed when the OS Maps website became available online. This is the replacement for OS Get-a-map and has contours at 5m intervals which are proving consistently more accurate compared to the 5m contours that sometimes appear on Ordnance Survey 1:25,000 Explorer maps and used to appear on the online Vector Map Local. This re-assessment resulted in the estimated bwlch height for this hill remaining the same at c 304m, with this based on interpolation of 5m contouring between 300m – 305m.
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 confirmation of the addition of this hill to Sub-Trichant status is due to LIDAR analysis which only covers the summit area and detail derived from contemporary maps produced from Ordnance Survey data, resulting in a 324.6m summit height and a c 304m bwlch height, with these values giving this hill c 21m 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: Foel
OS 1:50,000 map: 116
Summit Height: 324.6m (LIDAR)
Summit Grid Reference: SJ 07414 52102 & SJ 07416 52103 (LIDAR)
Bwlch Height: c 304m (interpolation)
Bwlch Grid Reference: SJ 07133 52262 (interpolation)
Drop: c 21m (LIDAR summit and interpolated bwlch)
Myrddyn Phillips (June 2020)
Boncyn Nadroedd (SJ 027 540) – Sub-Trichant addition (55th 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 derived from detail on contemporary maps produced from Ordnance Survey data.
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 Boncyn Nadroedd 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 minor roads to its north, west and east, and has the town of Rhuthun (Ruthin) towards the east 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 not included in the Hills to be surveyed sub list that accompanied the main P30 list, as it was considered not to 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 and it was listed with an estimated c 23m of drop, based on interpolated values of c 390m and c 367m for its summit and bwlch respectively, with each based on interpolation of 10m contouring on the Ordnance Survey 1:25,000 Explorer map.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
The details for this hill were re-assessed when the OS Maps website became available online. This is the replacement for OS Get-a-map and has contours at 5m intervals which are proving consistently more accurate compared to the 5m contours that sometimes appear on Ordnance Survey 1:25,000 Explorer maps and used to appear on the online Vector Map Local. This re-assessment resulted in the estimated bwlch height for this hill being amended to c 368m, with this based on interpolation of 5m contouring between 365m – 370m.
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| Extract from the Magic Maps website |
The details for this hill were also re-assessed against Ordnance Survey data hosted on the Magic Maps website as well as the WalkLakes website, and what was thought to be a tiny uppermost 390m summit ring contour is given a 389m spot height on these two interactive maps, implying that what was taken as a small ring contour on the Ordnance Survey 1:25,000 Explorer map, is in fact a spot height missing its 389m height.
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| Extract from the WalkLakes website |
Therefore, the confirmation of the addition of this hill to Sub-Trichant status is due to detail derived from contemporary maps produced from Ordnance Survey data, resulting in a 389m summit height and a c 368m bwlch height, with these values giving this hill c 21m 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: Boncyn Nadroedd
OS 1:50,000 map: 116
Summit Height: 389m (spot height)
Summit Grid Reference: SJ 02740 54035 (spot height)
Bwlch Height: c 368m (interpolation)
Bwlch Grid Reference: SJ 02565 54068 (interpolation)
Drop: c 21m (spot height summit and interpolated bwlch)
Mapping Mountains - Hill Reclassifications - Y Trichant
Ffridd Cerrig Cae Newydd (SH 829 633) – Sub-Trichant reclassified to Trichant (54th reclassification)
Significant Name Changes post for Ffridd Cerrig Cae Newydd
There has been confirmation of 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 detail on contemporary Ordnance Survey maps.
The criteria for the list that this reclassification 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 Ffridd Cerrig Cae Newydd and this was derived from the Tithe map, 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 A548 road to its north-west and the B5113 road to its east, and has the town of Llanrwst towards the west 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 accompanying Hills to be surveyed sub list, as it was considered not to 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 with an estimated c 27m of drop, based on the 302m summit spot height that appears on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map and an estimated c 275m bwlch height, with the latter based on interpolation of 10m contouring between 270m – 280m.
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| Extract from the 1:25,000 Explorer map |
The details for this hill were re-assessed when the Ordnance Survey Vector Map Local hosted on the Geograph website and which is entitled the Interactive Coverage Map became available online. This mapping had many spot heights not on other publicly available Ordnance Survey maps and showed a 272m spot height on the bwlch area of this hill. This spot height is also shown on Ordnance Survey data that appears on the Magic Maps website, and when coupled with the 302m summit spot height gives this hill 30m of drop.
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| Extract from the Magic Maps website |
Therefore, the reclassification of this hill from Sub-Trichant status is due to detail derived from contemporary maps produced from Ordnance Survey data, resulting in a 302m summit height and a 272m bwlch height, with these values giving this hill 30m of drop, which is sufficient for it to be classified as a Trichant.
The full details for the hill are:
Group: Mynydd Hiraethog
Name: Ffridd Cerrig Cae Newydd
OS 1:50,000 map: 116
Summit Height: 302m (spot height)
Summit Grid Reference: SH 82967 63328 (hand-held GPS via DoBIH)
Bwlch Height: 272m (spot height)
Bwlch Grid Reference: SH 83181 63238 (spot height)
Drop: 30m (spot height summit and bwlch)
Myrddyn Phillips (May 2020)
Ffridd Fawr (SH 914 642) – Sub-Trichant reclassified to Trichant (53rd reclassification)
Significant Name Changes post for Ffridd Fawr
There has been confirmation of 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 detail on contemporary Ordnance Survey maps.
The criteria for the list that this reclassification 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 Ffridd Fawr and this was derived from the Tithe map, 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 B5384 road to its north-west, the A543 road to its south and the A544 road to its east, and has the village of Llansannan 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 that accompanied the main P30 list, as it was considered not to meet the criteria then used for the main P30 list.
 |
| 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 and it was listed with an estimated c 29m of drop, based on a 317m summit spot height that appears on the Ordnance Survey 1:50,000 Landranger map and an estimated c 288m bwlch height, with the latter based on interpolation of 10m contouring between 280m – 290m.
 |
| Extract from the Ordnance Survey 1:50,000 Landranger map |
The details for this hill were re-assessed when the Ordnance Survey Vector Map Local hosted on the Geograph website and which is entitled the Interactive Coverage Map became available online. This mapping had many spot heights not on other publicly available Ordnance Survey maps and showed a 318m spot height on the summit area of this hill. This spot height is also shown on Ordnance Survey data that appears on the Magic Maps website, and when coupled with the c 288m bwlch height gives this hill c 30m of drop.
 |
| Extract from the Magic Maps website |
Therefore, the reclassification of this hill from Sub-Trichant status is due to detail derived from contemporary maps produced from Ordnance Survey data, resulting in a 318m summit height and a c 288m bwlch height, with these values giving this hill c 30m of drop, which is sufficient for it to be classified as a Trichant.
The full details for the hill are:
Group: Mynydd Hiraethog
Name: Ffridd Fawr
OS 1:50,000 map: 116
Summit Height: 318m (spot height)
Summit Grid Reference: SH 91406 64254 (hand-held GPS via DoBIH)
Bwlch Height: c 288m (interpolation)
Bwlch Grid Reference: SH 91154 63416 (interpolation)
Drop: c 30m (spot height summit and interpolated bwlch)
Myrddyn Phillips (May 2020)
Ffridd Fawr (SH 911 637) – Sub-Trichant addition (52nd reclassification)
Significant Name Changes post for Ffridd Fawr
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 derived from detail on contemporary Ordnance Survey maps.
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 Ffridd Fawr and this was derived from the Tithe map, 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 B5384 road to its north-west and the A544 road to its east, and has the village of Llansannan 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 not included in the Hills to be surveyed sub list that accompanied the main P30 list, as it was considered not to 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 against the Ordnance Survey Vector Map Local hosted on the Geograph website and which is entitled the Interactive Coverage Map. This mapping had many spot heights not on other publicly available Ordnance Survey maps and included a 309m summit and 289m bwlch spot height for this hill. These spot heights are also shown on Ordnance Survey data that appears on the Magic Maps website.
 |
| Extract from the Magic Maps website |
Therefore, the addition of this hill to Sub-Trichant status is due to detail derived from the Ordnance Survey Vector Map Local hosted on the Geograph website and which is entitled the Interactive Coverage Map, with this detail also shown on the Magic Maps website, resulting in a 309m summit height and a 289m bwlch height, with these values giving this hill 20m 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: Ffridd Fawr
OS 1:50,000 map: 116
Summit Height: 309m (spot height)
Summit Grid Reference: SH 91105 63732 (spot height)
Bwlch Height: 289m (spot height)
Bwlch Grid Reference: SH 91260 63693 (spot height)
Drop: 20m (spot height summit and bwlch)
Myrddyn Phillips (April 2020)
Mapping Mountains - Hill Reclassifications - Y Trichant
Ysgeibion (SJ 060 589) – Sub-Trichant addition (51st reclassification)
Significant Name Changes post for Ysgeibion
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 derived from detail on contemporary Ordnance Survey maps.
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 Ysgeibion and this was derived from the Tithe map, 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 encircled by minor roads with the B4501 road further to its north-west, the B5105 road further to its south-east and the A525 road further to its north-east, and has the town of Rhuthun (Ruthin) 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 was considered not to 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 and it was listed with c 21m of drop, based on the 338m spot height that appears on the Ordnance Survey 1:25,000 Explorer map and an estimated c 317m bwlch height based on interpolation of 5m contouring between 315m – 320m.
 |
| Extract from the Ordnance Survey 1:25,000 Explorer map |
Another resource now available online is the WalkLakes website which hosts an interactive map originated from the Ordnance Survey Open Data programme. This map has many spot heights not on other publicly available maps and shows a 339m spot height on the summit area of this hill. However, for this hill the 338m spot height shown on the Ordnance Survey 1:25,000 Explorer map is being prioritised.
 |
| Extract from the WalkLakes website |
Therefore, the addition of this hill to Sub-Trichant status is due to detail derived from contemporary Ordnance Survey maps, resulting in a 338m summit height and a c 317m bwlch height, with these values giving this hill an estimated c 21m 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: Ysgeibion
OS 1:50,000 map: 116
Summit Height: 338m (spot height)
Summit Grid Reference: SJ 06079 58984 (spot height)
Bwlch Height: c 317m (interpolation)
Bwlch Grid Reference: SJ 05734 59177 (interpolation)
Drop: c 21m (spot height summit and interpolated bwlch)
Myrddyn Phillips (April 2020)
Craig Arthbry (SJ 031 455) – Trichant reclassified to Sub-Trichant (50th 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 confirmed by LIDAR analysis conducted by Myrddyn Phillips.
 |
| LIDAR image of Craig Arthbry (SJ 031 455) |
The criteria for the list that this reclassification 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 Craig Arthbry, 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 has the B5105 road to its north-west, the A5 road to its south and the A494 road to its east, and has the town of Corwen towards the east 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 included in the Hills to be surveyed sub list that accompanied the main P30 list, as it was considered not to 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 with an estimated c 30m of drop, based on the 317m spot height that appears on the Ordnance Survey 1:25,000 Explorer map and an estimated bwlch height of c 287m based on interpolation of 10m contouring between 280m – 290m.
 |
| 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 had many spot heights not on other publicly available Ordnance Survey maps and in certain areas also included 5m contouring. As this mapping has a 286m spot height in the area of this hill’s bwlch, the drop value was revised to 31m. This spot height is also shown on Ordnance Survey data that appears on the Magic Maps website.
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| Extract from the Magic 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.
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| LIDAR summit image for Craig Arthbry |
Therefore, the reclassification of this hill from Trichant status is due to LIDAR analysis, resulting in a 315.4m summit height and a 286.8m bwlch height, with these values giving this hill 28.6m 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: Craig Arthbry
OS 1:50,000 map: 116
Summit Height: 315.4m (LIDAR)
Summit Grid Reference: SJ 03112 45567 (LIDAR)
Bwlch Height: 286.8m (LIDAR)
Bwlch Grid Reference: SJ 03460 45898 (LIDAR)
Drop: 28.6m (LIDAR)
Myrddyn Phillips (April 2020)
Bryniau Gleision (SH 842 680) – Sub-Trichant addition (49th 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 derived from detail on contemporary Ordnance Survey maps.
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 Bryniau Gleision, and it is adjoined to the Rhos group of hills which are situated in the northern part of North Wales (Region A, Sub-Region A2), and it is positioned with the B5113 road to its west and the A548 road to its south and east, and has the town of Llanrwst 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 was considered not to 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 and it was listed with 20m of drop, based on the 333m spot height that appears on the Ordnance Survey 1:50,000 Landranger map and the 313m spot height that appears on the area of this hill’s bwlch on the Ordnance Survey 1:25,000 Explorer map.
 |
| Extract from the Ordnance Survey 1:50,000 Landranger 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 had many spot heights not on other publicly available Ordnance Survey maps, and also sometimes included 5m contouring. As this mapping showed a small uppermost 335m ring contour the summit height of this hill was revised to an estimated c 335m.
The details for this hill were also re-assessed when the OS Maps website became available online. This is the replacement for OS Get-a-map and has contours at 5m intervals which are proving consistently more accurate compared to the 5m contours that sometimes appear on Ordnance Survey 1:25,000 Explorer maps and used to appear on the online Vector Map Local. This re-assessment resulted in the hill being listed with an estimated c 313m bwlch height with an interpolated position considered more accurate than the position of the 313m spot height, with this based on interpolation of 5m contouring between 310m – 315m.
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| Extract from the OS Maps website |
Therefore, the addition of this hill to Sub-Trichant status is due to detail derived from contemporary Ordnance Survey maps, resulting in a c 335m summit height and a c 313m bwlch height, with these values giving this hill an estimated c 22m of drop, which is sufficient for it to be classified as a Sub-Trichant.
The full details for the hill are:
Group: Rhos
Name: Bryniau Gleision
OS 1:50,000 map: 116
Summit Height: c 335m (interpolation)
Summit Grid Reference: SH 84224 68029 (interpolation)
Bwlch Height: c 313m (interpolation)
Bwlch Grid Reference: SH 83865 68223 (interpolation)
Drop: c 22m (interpolation)
Myrddyn Phillips (March 2020)
Wenlli (SH 845 655) – Sub-Trichant reclassified to Trichant (48th reclassification)
Significant Name Changes post for Wenlli
Summit Relocations post for Wenlli
There has been confirmation of 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 detail on contemporary Ordnance Survey maps.
 |
| LIDAR image of Wenlli (SH 845 655) |
The criteria for the list that this reclassification 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 now listed by is Wenlli and this was derived from the Tithe map, and it is adjoined to the Rhos group of hills which are situated in the northern part of North Wales (Region A, Sub-Region A2), and it is positioned with the B5113 road to its west and the A548 road to its south and east, and has the town of Llanrwst 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 was considered not to meet the criteria then used for the main P30 list.
 |
| 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 and it was listed with an estimated c 30m of drop, based on the twin 308m map heighted summits with the prioritised summit position given to the spot height that appears at SH 846 654 on Ordnance Survey 1:25,000 Explorer maps, and an estimated c 278m bwlch height.
The details for this hill were re-examined when the Ordnance Survey Vector Map Local hosted on the Geograph website and which is entitled the Interactive Coverage Map became available online. This mapping had many spot heights not on other publicly available Ordnance Survey maps. However, as this mapping had no additional spot heights of note the details for this hill remained the same.
The details for this hill were also re-assessed when the OS Maps website became available online. This is the replacement for OS Get-a-map and has contours at 5m intervals which are proving consistently more accurate compared to the 5m contours that sometimes appear on Ordnance Survey 1:25,000 Explorer maps and used to appear on the online Vector Map Local. This re-assessment resulted in the hill being listed with an estimated c 277m bwlch height based on interpolation of 5m contouring between 275m – 280m and therefore increasing its drop value to c 31m.
During these re-assessments the position of this hill’s summit was relocated to match a hand-held GPS position submitted to DoBIH, and although an accurate survey would be needed to confirm this position, for now it is being taken for that of the summit.
Therefore, the reclassification of this hill from Sub-Trichant status is due to detail derived from contemporary Ordnance Survey maps, resulting in a 308m summit height and an estimated 277m bwlch height, with these values giving this hill c 31m of drop, which is sufficient for it to be classified as a Trichant.
The full details for the hill are:
Group: Rhos
Name: Wenlli
OS 1:50,000 map: 116
Summit Height: 308m (spot height)
Summit Grid Reference: SH 84520 65553 (hand-held GPS via DoBIH)
Bwlch Height: c 277m (interpolation)
Bwlch Grid Reference: SH 83917 65689 (interpolation)
Drop: c 31m (hand-help GPS via DoBIH and interpolated bwlch)
Myrddyn Phillips (March 2020)
Foel Caledeiriau (SH 838 668) – Sub-Trichant addition (47th 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 derived from detail on contemporary maps produced from Ordnance Survey data.
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 Foel Caledeiriau and it is adjoined to the Rhos group of hills which are situated in the northern part of North Wales (Region A, Sub-Region A2), and it is positioned with the B5113 road to its west and the A548 road to its south and its east, and has the town of Llanrwst 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 was considered not to 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-assessed using the Ordnance Survey 1:25,000 Explorer map and the Ordnance Survey Vector Map Local hosted on the Geograph website and which is entitled the Interactive Coverage Map. The latter mapping had many spot heights not on other publicly available Ordnance Survey maps and for this hill is had a 293m spot height on the area of the bwlch, this spot height also appears on the Magic Maps website, and when coupled with the 318m summit height that appears as a spot height on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map gives this hill 25m of drop.
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| Extract from the Magic Maps website |
Therefore, the addition of this hill to Sub-Trichant status is due to detail derived from contemporary maps produced from Ordnance Survey data, resulting in a 318m summit height and a 293m bwlch height, with these values giving this hill 25m of drop, which is sufficient for it to be classified as a Sub-Trichant.
The full details for the hill are:
Group: Rhos
Name: Foel Caledeiriau
OS 1:50,000 map: 116
Summit Height: 318m (spot height)
Summit Grid Reference: SH 83897 66863 (spot height)
Bwlch Height: 293m (spot height)
Bwlch Grid Reference: SH 83762 67171 (spot height)
Drop: 25m (spot heights)
Myrddyn Phillips (March 2020)
Coed Bryndansi (SH 855 740) – Sub-Trichant reclassified to Trichant (46th reclassification)
There has been confirmation of 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 detail on contemporary maps produced from Ordnance Survey data.
The criteria for the list that this reclassification 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 Coed Bryndansi and it is adjoined to the Rhos group of hills which are situated in the northern part of North Wales (Region A, Sub-Region A2), and it is positioned with the B5381 road to its north, the B5113 road to its west and minor roads to its south and east, and has the village of Llansanffraid Glan Conwy towards the west 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 included in the Hills to be surveyed sub list that accompanied the main P30 list, as it was considered not to 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 estimated with c 27m of drop, based on an estimated c 303m summit height and an estimated c 276m bwlch height with the latter based on interpolation of 10m contouring between 270m – 280m.
 |
| Extract from the Ordnance Survey 1:25,000 Explorer map |
The details for this hill were re-assessed when the Ordnance Survey Vector Map Local hosted on the Geograph website and which is entitled the Interactive Coverage Map became available online. This mapping had many spot heights not on other publicly available Ordnance Survey maps and also for this area it had contour intervals at 5m. This re-assessment resulted in this hill being listed with c 30m of drop based on an estimated c 303m summit height and an estimated c 273m bwlch height with the latter based on interpolation of 5m contouring between 270m – 275m.
The details for this hill were also re-assessed when the OS Maps website became available online. This is the replacement for OS Get-a-map and has contours at 5m intervals which are proving consistently more accurate compared to the 5m contours that sometimes appear on Ordnance Survey 1:25,000 Explorer maps and used to appear on the online Vector Map Local. This latest re-assessment also resulted in an estimated bwlch height of c 273m resulting in a drop value of c 30m.
The estimated summit height was substantiated when the Ordnance Survey series of Six-Inch maps were examined, as this mapping shows a 995.1ft (303.1m) Surface height for this hill.
 |
| Extract from the Ordnance Survey series of Six-Inch maps |
When the Ordnance Survey Vector Map Local that was hosted on the Geograph website and entitled the Interactive Coverage Map became unavailable it was replaced with another Ordnance Survey product that showed a number of spot heights not on other publicly available Ordnance Survey maps. This latest mapping does not have contours, but for this hill it shows a 304m summit spot height positioned at SH 85567 74121, which corresponds with the approximate position of the aforementioned Surface height.
 |
| Extract from the Ordnance Survey non-contour Vector Map Local hosted on the Geograph wbsite |
Another resource now available online is the WalkLakes website which hosts an interactive map originated from the Ordnance Survey Open Data programme. This map has many spot heights not on other publicly available Ordnance Survey maps and for this hill it shows a 305m summit spot height positioned at SH 85531 74002.
 |
| Extract from the WalkLakes website |
Therefore, the confirmation of the reclassification of this hill to Trichant status is due to detail derived from contemporary maps produced from Ordnance Survey data, resulting in a 305m summit height and an estimated bwlch height of c 273m, with these values giving this hill c 32m of drop, which is sufficient for it to be classified as a Trichant.
The full details for the hill are:
Group: Rhos
Name: Coed Bryndansi
OS 1:50,000 map: 116
Summit Height: 305m (spot height)
Summit Grid Reference: SH 85531 74002 (spot height)
Bwlch Height: c 273m (interpolation)
Bwlch Grid Reference: SH 85239 74303 (interpolation)
Drop: c 32m (spot height summit and interpolated bwlch)
Myrddyn Phillips (March 2020)
Fron Gynnen (SH 835 717) – Sub-Trichant addition (45th 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 derived from detail on contemporary Ordnance Survey maps.
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 Fron Gynnen and it is adjoined to the Rhos group of hills which are situated in the northern part of North Wales (Region A, Sub-Region A2), and it is positioned with minor roads to its north, west and south and the B5113 road to its east, and has the village of Llansanffraid Glan Conwy 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 was considered not to 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 and it was estimated with c 23m of drop, based on the 316m summit spot height that appears on the Ordnance Survey 1:50,000 Landranger map and an estimated bwlch height of c 293m based on interpolation of 10m contouring between 290m – 300m.
 |
| Extract from the Ordnance Survey 1:50,000 Landranger map |
The details for this hill were re-assessed when the Ordnance Survey Vector Map Local hosted on the Geograph website and which is entitled the Interactive Coverage Map became available online. This mapping had many spot heights not on other publicly available Ordnance Survey maps and also for this area it had contour intervals at 5m. However, interpolation using this mapping also suggested an estimated bwlch height of c 293m.
The details for this hill were also re-assessed when the OS Maps website became available online. This is the replacement for OS Get-a-map and has contours at 5m intervals which are proving consistently more accurate compared to the 5m contours that sometimes appear on Ordnance Survey 1:25,000 Explorer maps and used to appear on the online Vector Map Local. This latest re-assessment also resulted in an estimated bwlch height of c 293m.
 |
| Extract from the OS Maps website |
Therefore, the confirmation of the addition of this hill to Sub-Trichant status is due to detail on contemporary Ordnance Survey maps, resulting in a 316m summit height and a c 293m bwlch height, with these values giving this hill c 23m of drop, which is sufficient for it to be classified as a Sub-Trichant.
The full details for the hill are:
Group: Rhos
Name: Fron Gynnen
OS 1:50,000 map: 116
Summit Height: 316m (spot height)
Summit Grid Reference: SH 83539 71740 (spot height)
Bwlch Height: c 293m (interpolation)
Bwlch Grid Reference: SH 84066 71024 (interpolation)
Drop: c 23m (spot height summit and interpolated bwlch)
Myrddyn Phillips (February 2020)
Mapping Mountains - Hill Reclassifications - Y Trichant
Ffridd y Graig (SH 863 704) – Sub-Trichant addition (44th reclassification)
Significant Name Changes post for Ffridd y Graig
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 derived from detail on contemporary Ordnance Survey maps.
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 Ffridd y Graig and this was derived from the Tithe map, and it is adjoined to the Rhos group of hills which are situated in the northern part of North Wales (Region A, Sub-Region A2), and it is encircled by minor roads with the B5113 farther to the west and the A548 farther to the south-east, and has the village of Llangernyw towards the south 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 that accompanied the main P30 list, as it was considered not to 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 and it was estimated with c 17m of drop, based on interpolation of the uppermost 300m ring contour giving an estimated summit height of c 303m and an estimated bwlch height of c 286m based on interpolation of 10m contouring between 280m – 290m.
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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 Vector Map Local hosted on the Geograph website and which is entitled the Interactive Coverage Map became available online. This mapping had many spot heights not on other publicly available Ordnance Survey maps and also for this area it had contour intervals at 5m. Therefore, the drop value was amended to an estimated c 21m based on interpolation of bwlch contouring between 280m – 285m.
The details for this hill were also re-assessed when the OS Maps website became available online. This is the replacement for OS Get-a-map and has contours at 5m intervals which are proving consistently more accurate compared to the 5m contours that sometimes appear on Ordnance Survey 1:25,000 Explorer maps and used to appear on the online Vector Map Local. This latest re-assessment resulted in the hill being listed with an estimated c 20m of drop, based on an estimated c 304m summit height and an estimated c 284m bwlch height.
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| Extract from the OS Maps website |
Therefore, the confirmation of the addition of this hill to Sub-Trichant status is due to detail on contemporary Ordnance Survey maps, resulting in an estimated c 304m summit and c 284m bwlch height, 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: Rhos
Name: Ffridd y Graig
OS 1:50,000 map: 116
Summit Height: c 304m (interpolation)
Summit Grid Reference: SH 86341 70410 (interpolation)
Bwlch Height: c 284m (interpolation)
Bwlch Grid Reference: SH 86461 70442 (interpolation)
Drop: c 20m (interpolation)
Myrddyn Phillips (February 2020)
Mapping Mountains - Hill Reclassifications - Y Trichant
Mynydd Dir (SH 915 712) – Sub-Trichant reclassified to Trichant (43rd reclassification)
There has been confirmation of 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 detail on contemporary Ordnance Survey maps.
The criteria for the list that this reclassification 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 Dir, and it is adjoined to the Rhos group of hills which are situated in the northern part of North Wales (Region A, Sub-Region A2), and it is positioned with the B4381 road to its north and the A548 road to its south and east, and has the village of Llanfair Talhaiarn towards the 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 included in the Hills to be surveyed sub list that accompanied the main P30 list, as it was considered not to 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 with an estimated c 30m of drop, based on the 314m summit spot height that appears on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map and an estimated bwlch height of c 284m based on interpolation of 10m contouring between 280m – 290m.
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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 Vector Map Local hosted on the Geograph website and which is entitled the Interactive Coverage Map became available online. This mapping had many spot heights not on other publicly available Ordnance Survey maps and also for this area it had contour intervals at 5m. Therefore, the drop value was amended to an estimated c 32m based on interpolation of bwlch contouring between 280m – 285m.
The details for this hill were also re-assessed when the OS Maps website became available online. This is the replacement for OS Get-a-map and has contours at 5m intervals which are proving consistently more accurate compared to the 5m contours that sometimes appear on Ordnance Survey 1:25,000 Explorer maps and used to appear on the online Vector Map Local. This latest re-assessment resulted in the hill being listed with an estimated c 36m of drop, based on interpolation of 5m bwlch contouring between 275m – 280m.
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| Extract from the OS Maps website |
Therefore, the confirmation of the reclassification of this hill from Sub-Trichant status is due to detail on contemporary Ordnance Survey maps, resulting in a 314m summit height and an estimated c 278m bwlch height, with these values giving this hill c 36m of drop, which is sufficient for it to be classified as a Trichant.
The full details for the hill are:
Group: Rhos
Name: Mynydd Dir
OS 1:50,000 map: 116
Summit Height: 314m (spot height)
Summit Grid Reference: SH 91597 71238 (hand-held GPS via DoBIH)
Bwlch Height: c 278m (interpolation)
Bwlch Grid Reference: SH 91337 71524 (interpolation)
Drop: c 36m (spot height summit and interpolated bwlch)
Myrddyn Phillips (February 2020)
Yr Arddu (SH 626 462) – Sub-Trichant addition (42nd 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 derived from spot heights on contemporary Ordnance Survey maps.
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 Yr Arddu, and it is adjoined to the Moelwynion group of hills which are situated in the north-western part of North Wales (Region A, Sub-Region A1), and it is positioned with the A498 road to its north-west and the A4085 road to its south-west, and has the village of Beddgelert towards the west 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 was considered not to 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 and it was listed with an estimated c 26m of drop, based on the 389m summit spot height that appears on the Ordnance Survey 1:50,000 Landranger map and an estimated bwlch height of c 363m based on interpolation of 10m contouring between 360m – 370m.
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| Extract from the Ordnance Survey 1:50,000 Landranger map |
The details for this hill were re-assessed when the Ordnance Survey Vector Map Local hosted on the Geograph website and which is entitled the Interactive Coverage Map became available online. This mapping had many spot heights not on other publicly available Ordnance Survey maps and included a 362m spot height on the area of this hill’s bwlch. This spot height is also shown on Ordnance Survey data that appears on the Magic Maps website.
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| Extract from the Magic Maps website |
Therefore, the addition of this hill to Sub-Trichant status is due to spot heights on contemporary Ordnance Survey maps, resulting in a 389m summit height and a 362m bwlch height, with these values giving this hill 27m of drop which is sufficient for it to be classified as a Sub-Trichant.
The full details for the hill are:
Group: Moelwynion
Name: Yr Arddu
OS 1:50,000 map: 115
Summit Height: 389m (spot height)
Summit Grid Reference: SH 62652 46230 (spot height)
Bwlch Height: 362m (spot height)
Bwlch Grid Reference: SH 62863 46313 (spot height)
Drop: 27m (spot heights)
Myrddyn Phillips (February 2020)
Nyrs Fawr (SH 867 008) – Sub-Trichant addition (41st reclassification)
Survey post for Nyrs Fawr
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 a Trimble GeoXH 6000 survey conducted by Myrddyn Phillips on the 29th October 2019.
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| Nyrs Fawr (SH 867 008) |
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 Nyrs Fawr and it is adjoined to the Pumlumon group of hills which are situated in the northern part of Mid and West Wales (Region B, Sub-Region B2), and it is positioned with the Afon Twymyn and the A470 road to its north and the B4518 road to its east, and has the village of Llanbrynmair towards the north-east.
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| Gathering data at the summit of Nyrs Fawr |
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| Gathering data at the bwlch of Nyrs Fawr |
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 was considered not to 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 and it was listed with an estimated c 23m of drop, based on the 365m 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 10m contouring between 340m – 350m.
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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 Vector Map Local hosted on the Geograph website and which is entitled the Interactive Coverage Map became available online. This mapping had many spot heights not on other publicly available Ordnance Survey maps and included a 344m spot height on the area of this hill’s bwlch which decreased the listed drop to 21m. This spot height is also shown on Ordnance Survey data that appears on the Magic Maps website. However, it was not until the survey with the Trimble GeoXH 6000 that the status of this hill could be confirmed.
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| Extract from the Magic Maps website |
Therefore, the confirmation of the addition of this hill to Sub-Trichant status is due to a Trimble GeoXH 6000 survey, resulting in a 363.8m summit height and a 340.9m bwlch height, with these values giving this hill 22.9m of drop which is sufficient for it to be classified as a Sub-Trichant.
The full details for the hill are:
Group: Pumlumon
Name: Nyrs Fawr
OS 1:50,000 map: 135, 136
Summit Height: 363.8m (converted to OSGM15)
Summit Grid Reference: SH 86771 00895
Bwlch Height: 340.9m (converted to OSGM15)
Bwlch Grid Reference: SH 86860 00561
Drop: 22.9m
Myrddyn Phillips (February 2020)
Pt. 316.1m (SH 608 479) – Sub-Trichant addition (40th 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 by LIDAR analysis conducted by Myrddyn Phillips.
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| LIDAR image of Pt. 316.1m (SH 608 479) |
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. 316.1m) 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 Moelwynion group of hills which are situated in the north-western part of North Wales (Region A, Sub-Region A1), and it is positioned with the Afon Glaslyn and the A498 road to its north and west, and has the village of Beddgelert towards the 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 was considered not to meet the criteria then used for this sub category.
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| 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 and it was listed with an estimated c 19m of drop, based on the 315m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and an estimated bwlch height of c 296m based on interpolation of contouring between 290m – 300m.
The details for this hill were re-assessed 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 other publicly available Ordnance Survey maps.
The details for this hill were also re-assessed when the OS Maps website became available online. This is the replacement for OS Get-a-map and has contours at 5m intervals which are proving consistently more accurate compared to the 5m contours that sometimes appear on Ordnance Survey 1:25,000 Explorer maps and used to appear on the online Vector Map Local. These re-assessments resulted in the hill remaining with an estimated drop of c 19m.
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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.
Therefore, the addition of this hill to Sub-Trichant status is due to LIDAR analysis, resulting in a 316.1m summit height and a 296.0m 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: Moelwynion
Name: Pt. 316.1m
OS 1:50,000 map: 115
Summit Height: 316.1m (LIDAR)
Summit Grid Reference: SH 60849 47935 (LIDAR)
Bwlch Height: 296.0m (LIDAR)
Bwlch Grid Reference: SH 60963 47863 (LIDAR)
Drop: 20.1m (LIDAR)
Myrddyn Phillips (January 2020)
Moel Smytho (SH 520 576) – Sub-Trichant reclassified to Trichant (39th reclassification)
There has been confirmation of 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 confirmed by LIDAR analysis conducted by Myrddyn Phillips.
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| LIDAR image of Moel Smytho (SH 520 576) |
The criteria for the list that this reclassification 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 Moel Smytho and it is adjoined to the Moel Hebog group of hills which are situated in the north-western part of North Wales (Region A, Sub-Region A1), and it is positioned with the Afon Gwyrfai and the A4085 road to its north-east, and has the village of Waunfawr towards the north.
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 was considered not to meet the criteria then used for the main P30 category.
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 with an estimated c 30m of drop, based on the 343m summit spot height that appears on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map and an estimated bwlch height of c 313m based on interpolation of contouring between 310m – 320m.
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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 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 other publicly available Ordnance Survey maps and gives a 311m spot height on the area of this hill’s bwlch. This spot height is also shown on Ordnance Survey data that appears on the Magic Maps website. The bwlch spot height coupled with the 343m summit spot height confirmed this hill’s Trichant status with 32m of listed drop.
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| Extract from the Magic 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 reclassification of Moel Smytho from Sub-Trichant status is due to LIDAR analysis, resulting in a 341.9m summit height and a 310.5m bwlch height, with these values giving this hill 31.4m of drop which is sufficient for it to be classified as a Trichant.
The full details for the hill are:
Group: Moel Hebog
Name: Moel Smytho
OS 1:50,000 map: 115
Summit Height: 341.9m (LIDAR)
Summit Grid Reference: SH 52096 57676 (LIDAR)
Bwlch Height: 310.5m (LIDAR)
Bwlch Grid Reference: SH 52151 57266 (LIDAR)
Drop: 31.4m (LIDAR)
Myrddyn Phillips (January 2020)
Graig (SO 299 237) – Sub-Trichant reclassified to Trichant (38th reclassification)
Significant Name Changes post for Graig
There has been confirmation of 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 confirmed by LIDAR analysis conducted by Myrddyn Phillips.
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| LIDAR summit image of Graig (SO 299 237) |
The criteria for the list that this reclassification 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 Graig and it is adjoined to the Mynyddoedd Duon group of hills which are situated in the eastern part of South Wales (Region C, Sub-Region C3), and it is positioned with minor roads to its west, south and east, with the A465 road further to its south-east, and has the small community of Cwmyoy 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 that accompanied the main P30 list, as it was considered not to 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 with an estimated c 28m of drop, based on an estimated c 346m summit height and an estimated c 318m bwlch height, with both based on interpolation of 10m contouring on the Ordnance Survey 1:25,000 Explorer map.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
The details for this hill were re-examined when the Ordnance Survey Vector Map Local hosted on the Geograph website and which is entitled the Interactive Coverage Map became available online. This mapping has many spot heights not on any other publicly available Ordnance Survey map and gives a 349m spot height on the summit area of this hill. This spot height is also shown on Ordnance Survey data that appears on the Magic Maps website. When coupled with the estimated c 318m bwlch height these values gave this hill c 31m of drop and the details of this hill’s new P30 status were subsequently posted on the RHB Yahoo Groups forum on the 30th June 2013.
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| Extract from the Magic Maps website |
During the re-assessment of this hill’s details the series of Ordnance Survey Six-Inch maps were examined and the origins of the 349m spot height can be traced back to the 1143.3ft (348.48m) surface height that appears on the 1887 map.
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| Extract from the series of Ordnance Survey Six-Inch maps |
However, it was not until LIDAR became available that the details for this hill could be accurately re-assessed. The LIDAR (Light Detection & Ranging) technique produced highly accurate height data that is now freely available for much of England and Wales.
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| LIDAR bwlch image for Graig |
The confirmation of the reclassification of Graig from Sub-Trichant status is due to LIDAR analysis, resulting in a 348.4m summit height and a 318.0m bwlch height, with these values giving this hill 30.4m of drop which is sufficient for it to be classified as a Trichant.
The full details for the hill are:
Group: Mynyddoedd Duon
Name: Graig
OS 1:50,000 map: 161
Summit Height: 348.4m (LIDAR)
Summit Grid Reference: SO 29983 23705 (LIDAR)
Bwlch Height: 318.0m (LIDAR)
Bwlch Grid Reference: SO 30011 23797 (LIDAR)
Drop: 30.4m (LIDAR)
Myrddyn Phillips (January 2020)
Pen Gallt y Llyn (SH 619 504) – Sub-Trichant addition (37th 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 by LIDAR analysis conducted by Myrddyn Phillips.
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| LIDAR image of Pen Gallt y Llyn (SH 619 504) |
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 Pen Gallt y Llyn and it is adjoined to the Yr Wyddfa group of hills which are situated in the north-western part of North Wales (Region A, Sub-Region A12), and it is positioned with the Afon Glaslyn and the A498 road to its south-east and Llyn Dinas towards its south, and has the village of Beddgelert 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 was considered not to 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 and it was listed with an estimated c 17m of drop, based on the 309m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and an estimated bwlch height of c 292m based on contouring between 290m – 300m.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
The details for this hill were re-examined when the Ordnance Survey Vector Map Local hosted on the Geograph website and which is entitled the Interactive Coverage Map became available online. This mapping has many spot heights not on any other publicly available Ordnance Survey map and gives a second 309m spot height on the summit area of this hill. This spot height is also shown on Ordnance Survey data that appears on the Magic Maps website. As this mapping did not have any additional spot heights at the bwlch area of this hill its listed drop remained as c 17m.
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| Extract from the Magic 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.
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| LIDAR image of Pen Gallt y Llyn (SH 619 504) |
The addition of Pen Gallt y Llyn to Sub-Trichant status is due to LIDAR analysis, resulting in a 309.1m summit height and a 289.0m 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: Yr Wyddfa
Name: Pen Gallt y Llyn
OS 1:50,000 map: 115
Summit Height: 309.1m (LIDAR)
Summit Grid Reference: SH 61964 50400 (LIDAR)
Bwlch Height: 289.0m (LIDAR)
Bwlch Grid Reference: SH 61833 50330 (LIDAR)
Drop: 20.1m (LIDAR)
Myrddyn Phillips (January 2020)
Yr Allt (SO 196 358) – Sub-Trichant reclassified to Trichant (36th reclassification)
Summit Relocations post for Yr Allt
Significant Name Changes post for Yr Allt
Summit Relocations post for Yr Allt
Significant Name Changes post for Yr Allt
There has been confirmation of 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 confirmed by LIDAR analysis conducted by Myrddyn Phillips.
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| LIDAR image of Yr Allt (SO 196 358) |
The criteria for the list that this reclassification 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 of the hill is Yr Allt and it is adjoined to the Mynyddoedd Duon group of hills which are situated in the eastern part of South Wales (Region C, Sub-Region C3), and it is positioned with minor roads to its west, north and east, with the A4078 road further to its west and the A438 road further to its north-west, and has the village of Aberllynfi (Three Cocks) 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 included in the Hills to be surveyed sub list that accompanied the main P30 list, as it was considered not to 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 with an estimated c 31m of drop, based on an estimated c 335m summit height and an estimated c 304m bwlch height.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
The details for this hill were re-examined when the Ordnance Survey Vector Map Local hosted on the Geograph website and which is entitled the Interactive Coverage Map became available online. This mapping has many spot heights not on any other publicly available Ordnance Survey map and gives a 302m spot height on the area of this hill’s bwlch. This spot height is also shown on Ordnance Survey data that appears on the Magic Maps website.
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| Extract from Ordnance Survey data hosted on the Magic Maps website |
During the re-assessment of this hill’s details the summit height was amended to 334m based on the 1096ft (334.06m) imperial height that appears on the summit area of this hill on the series of Ordnance Survey Six-Inch maps. These re-assessments resulted in the hill being listed with 32m of drop.
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| Extract from the series of Ordnance Survey Six-Inch maps |
However, it was not until LIDAR became available that the details for this hill could be accurately re-assessed. The LIDAR (Light Detection & Ranging) technique produced highly accurate height data that is now freely available for much of England and Wales.
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| LIDAR summit image of Yr Allt |
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| LIDAR bwlch image for Yr Allt |
The confirmation of the reclassification of Yr Allt from Sub-Trichant status is due to LIDAR analysis, resulting in a 334.0m height to a remaining natural summit and a 301.7m bwlch height, with these values giving this hill 32.3m of drop which is sufficient for it to be classified as a Trichant.
The full details for the hill are:
Group: Mynyddoedd Duon
Name: Yr Allt
OS 1:50,000 map: 161
Summit Height: 334.0m (LIDAR, natural summit)
Summit Grid Reference: SO 19677 35879 (LIDAR, natural summit)
Bwlch Height: 301.7m (LIDAR)
Bwlch Grid Reference: SO 20120 35549 (LIDAR)
Drop: 32.3m (LIDAR)
Myrddyn Phillips (December 2019)
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