Friday, 19 November 2021

Mapping Mountains - Hill Reclassifications - Y Trichant - The 300m Hills of Wales

 

Y Trichant - The 300m Hills of Wales – 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

Pared y Cefn Hir (SH 665 152) – Sub-Trichant addition (140th reclassification)

Significant Height Revisions post for Pared y Cefn Hir


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 LIDAR analysis conducted by Myrddyn Phillips. 

Pared y Cefn Hir (SH 665 152)

The criteria for the list that this addition applies to are: 

Y Trichant – The 300m Hills of Wales – Welsh hills at or above 300m and below 400m in height that have 30m minimum drop, with an accompanying sub list entitled the Sub-Trichant, with the criteria for this sub category being all Welsh hills at or above 300m and below 400m in height with 20m or more and below 30m of drop.  The list is authored by Myrddyn Phillips with the Introduction to the list and the renaming of it appearing on Mapping Mountains on the 13th May 2017, and the Introduction to the Mapping Mountains publication of the list appearing on the 1st January 2022. 

Y Trichant - The 300m Hills of Wales by Myrddyn Phillips

The name the hill is listed by is Pared y Cefn Hir, and it is adjoined to the Cadair Idris group of hills, which are situated in the south-western part of North Wales (Region A, Sub-Region A3), and it is positioned with the A493 road to its north-west and minor roads to its south-west, south-east and east, and has the town of Abermaw (Barmouth) 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, 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 an estimated c 15m of drop, based on an estimated c 374m summit height and an estimated c 359m bwlch height, with both heights based on interpolation of 10m contouring that appear on the Ordnance Survey 1:25,000 Explorer map. 

Extract from the Ordnance Survey 1:25,000 Explorer map

However, it was not until LIDAR became available that the details for this hill could be accurately re-assessed.  The LIDAR (Light Detection & Ranging) technique produced highly accurate height data that is now freely available for much of England and Wales. 

LIDAR image of Pared y Cefn Hir (SH 665 152)

Therefore, the addition of this hill to Sub-Trichant status is due to LIDAR analysis, resulting in a 379.0m summit height and a 358.4m bwlch height, with these values giving this hill 20.5m of drop, which is sufficient for it to be classified as a Sub-Trichant. 

 

The full details for the hill are: 

Group:  Cadair Idris 

Name:  Pared y Cefn Hir 

OS 1:50,000 map:  124

Summit Height:  379.0m (LIDAR)                                                           

Summit Grid Reference:  SH 66579 15214 (LIDAR) 

Bwlch Height:  358.4m (LIDAR) 

Bwlch Grid Reference:  SH 66538 15146 (LIDAR) 

Drop:  20.5m (LIDAR) 

 

Myrddyn Phillips (March 2022)

 

 


Mapping Mountains - Hill Reclassifications - Y Trichant

Pared y Cefn Hir (SH 661 148) – Sub-Trichant reclassified to Trichant (139th reclassification)

Trimble bwlch survey post for Pared y Cefn Hir


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 and a subsequent Leica GS15 survey conducted by John Barnard, Graham Jackson and Myrddyn Phillips. 

Pared y Cefn Hir (SH 661 148)

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, and the Introduction to the Mapping Mountains publication of the list appearing on the 1st January 2022. 

Y Trichant - The 300m Hills of Wales by Myrddyn Phillips

The name the hill is listed by is Pared y Cefn Hir, and it is adjoined to the Cadair Idris group of hills, which are situated in the south-western part of North Wales (Region A, Sub-Region A3), and it is positioned with the A493 road to its north-west and minor roads to its south-west, south-east and east, and has the town of Abermaw (Barmouth) 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, as it was considered not to meet the criteria then used for the main P30 category, with the 383m map heighted Bryn Brith (SH 664 153) listed as the prioritised P30. 

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 39m of drop, based on an estimated c 381m summit height and an estimated c 342 bwlch height, with both heights based on interpolation of 10m contouring that appear on the Ordnance Survey 1:25,000 Explorer map. 

Extract from the Ordnance Survey 1:25,000 Explorer map

Since the original publication of the Welsh P30 lists on Geoff Crowder’s v-g.me website there have been a number of maps made available online.  Some of these are historic such as the series of Six-Inch maps on the National Library of Scotland website.  Whilst others were digitally updated such as the Ordnance Survey Vector Map Local that was hosted on the Geograph website and which was entitled the Interactive Coverage Map, whilst others are current and digitally updated such as the interactive mapping on the Magic Maps and WalkLakes websites. 

The details for this hill were re-assessed when the Ordnance Survey Vector Map Local hosted on the Geograph website and which was entitled the Interactive Coverage Map became available online.  This mapping had many spot heights not on other publicly available Ordnance Survey maps and for this hill it had a 383m summit spot height and therefore it became twinned with the 383m map heighted Bryn Brith positioned at SH 664 153.  This spot height is also represented on the interactive mapping on the Magic Maps website. 

Extract from the Magic Maps website

Due to the twinning of Pared y Cefn Hir and Bryn Brith and the marginal Submarilyn status of the higher summit these hills were prioritised for a GNSS survey and this took place over two days and was conducted by John Barnard, Graham Jackson and Myrddyn Phillips using a Leica GS15, resulting in Pared y Cefn Hir being confirmed as the higher summit and the drop value confirmed as just below the 150m required for Marilyn status. 

Gathering data on the summit area of Pared y Cefn Hir with the offset between the set-up position and high point noted

Therefore, the confirmation of the reclassification of this hill from Sub-Trichant status is due to detail on contemporary maps produced from Ordnance Survey data and a subsequent Leica GS15 survey, resulting in a 383.1m summit height and a 233.7m bwlch height, with these values giving this hill 149.4m of drop, which is sufficient for it to be classified as a Trichant. 

 

The full details for the hill are: 

Group:  Cadair Idris 

Name:  Pared y Cefn Hir 

OS 1:50,000 map:  124

Summit Height:  383.1m (Leica GS15)                                                           

Summit Grid Reference:  SH 66199 14885 (Leica GS15) 

Bwlch Height:  233.7m (Leica GS15) 

Bwlch Grid Reference:  SH 65822 14423 (Leica GS15) 

Drop:  149.4m (Leica GS15) 

 

Myrddyn Phillips (March 2022)




Mapping Mountains - Hill Reclassifications - Y Trichant

Darren (SH 825 087) – Sub-Trichant addition (138th 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, and the Introduction to the Mapping Mountains publication of the list appearing on the 1st January 2022. 

Y Trichant - The 300m Hills of Wales by Myrddyn Phillips

The name the hill is listed by is Darren, and it is adjoined to the Aran Fawddwy group of hills, which are situated in the south-western part of North Wales (Region A, Sub-Region A3), and it is positioned with minor roads to its north and east, the A487 road to its west and the A470 road farther to its east, and has the town of Machynlleth 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, 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 29m of drop, based on the 324m summit spot height that appears on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map and the 295m bwlch spot height that appears on the Ordnance Survey 1:25,000 Explorer map. 

Extract from the Ordnance Survey 1:25,000 Explorer map

Since the original publication of the Welsh P30 lists on Geoff Crowder’s v-g.me website there have been a number of maps made available online.  Some of these are historic such as the series of Six-Inch maps on the National Library of Scotland website.  Whilst others were digitally updated such as the Ordnance Survey Vector Map Local that was hosted on the Geograph website and which was entitled the Interactive Coverage Map, whilst others are current and digitally updated such as the interactive mapping on the Magic Maps and WalkLakes websites. 

One of the resources recently available online is the mapping on the OS Maps website and the details for this hill were subsequently re-assessed against this mapping.  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 mapping had bwlch contouring between 295m – 300m, with interpolation placing the height of the bwlch as an estimated c 296m, with these contours also represented on other 5m contouring available online. 

Extract from online 5m contouring

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 324m summit height and an estimated c 296m bwlch height, with these values giving this hill an estimated c 28m of drop, which is sufficient for it to be classified as a Sub-Trichant. 

 

The full details for the hill are: 

Group:  Aran Fawddwy 

Name:  Darren 

OS 1:50,000 map:  124, 125

Summit Height:  324m (spot height)                                                           

Summit Grid Reference:  SH 82563 08709 (spot height) 

Bwlch Height:  c 296m (interpolation) 

Bwlch Grid Reference:  SH 82391 09148 (interpolation) 

Drop:  c 28m (spot height summit and interpolated bwlch) 

 

Myrddyn Phillips (February 2022)




Mapping Mountains - Hill Reclassifications - Y Trichant

Ffridd y Glyn (SH 816 080) – Sub-Trichant reclassified to Trichant (137th 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 LIDAR analysis conducted by Myrddyn Phillips and detail on contemporary maps produced from Ordnance Survey data. 

LIDAR image of Ffridd y Glyn (SH 816 080)

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, and the Introduction to the Mapping Mountains publication of the list appearing on the 1st January 2022. 

Y Trichant - The 300m Hills of Wales by Myrddyn Phillips

The name the hill is listed by is Ffridd y Glyn, and it is adjoined to the Aran Fawddwy group of hills, which are situated in the south-western part of North Wales (Region A, Sub-Region A3), and it is positioned with the A487 road to its west, the A489 road to its south and the A470 road to its east, and has the town of Machynlleth 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, as it was considered not to meet the criteria then used for the main P30 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 an estimated c 32m of drop, based on the 306m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and an estimated c 274m bwlch height, based on interpolation of 10m contouring between 270m – 280m. 

Extract from the Ordnance Survey 1:25,000 Explorer map

Since the original publication of the Welsh P30 lists on Geoff Crowder’s v-g.me website there have been a number of maps made available online.  Some of these are historic such as the series of Six-Inch maps on the National Library of Scotland website.  Whilst others were digitally updated such as the Ordnance Survey Vector Map Local that was hosted on the Geograph website and which was entitled the Interactive Coverage Map, whilst others are current such as the interactive mapping on the Magic Maps and WalkLakes websites. 

One of the resources recently available online is the mapping on the OS Maps website.  This is the replacement for OS Get-a-map and until recent times had contours at 5m intervals which were proving consistently more accurate compared to the 5m contours that sometimes appear on the Ordnance Survey 1:25,000 Explorer map and used to appear on the online Vector Map Local.  Although the mapping on the OS Maps website no longer has contours at 5m intervals, such contours are represented on other mapping available online and for this hill this mapping has bwlch contouring between 275m – 280m, with interpolation placing the height of the bwlch as an estimated c 276m. 

Extract from online 5m contouring

Therefore, the confirmation of the reclassification of this hill from Sub-Trichant status is due to LIDAR analysis and detail on contemporary maps produced from Ordnance Survey data, resulting in a 306.5m summit height and an estimated c 276m bwlch height, with these values giving this hill an estimated c 30m of drop, which is sufficient for it to be classified as a Trichant. 

 

The full details for the hill are: 

Group:  Aran Fawddwy 

Name:  Ffridd y Glyn 

OS 1:50,000 map:  124, 125

Summit Height:  306.5m (LIDAR)                                                           

Summit Grid Reference:  SH 81676 08091 (LIDAR) 

Bwlch Height:  c 276m (interpolation) 

Bwlch Grid Reference:  SH 81720 08732 (interpolation) 

Drop:  c 30m (LIDAR summit and interpolated bwlch) 

 

Myrddyn Phillips (February 2022)

 



Mapping Mountains - Hill Reclassifications - Y Trichant

Mynydd Pant Coch (SH 776 059) – Sub-Trichant deletion (136th reclassification)


There has been a deletion 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 deletion applies to are: 

Y Trichant – The 300m Hills of Wales – Welsh hills at or above 300m and below 400m in height that have 30m minimum drop, with an accompanying sub list entitled the Sub-Trichant, with the criteria for this sub category being all Welsh hills at or above 300m and below 400m in height with 20m or more and below 30m of drop.  The list is authored by Myrddyn Phillips with the Introduction to the list and the renaming of it appearing on Mapping Mountains on the 13th May 2017, and the Introduction to the Mapping Mountains publication of the list appearing on the 1st January 2022. 

Y Trichant - The 300m Hills of Wales by Myrddyn Phillips

The name the hill is listed by is Mynydd Pant Coch, and it is adjoined to the Aran Fawddwy group of hills, which are situated in the south-western part of North Wales (Region A, Sub-Region A3), and it is positioned with the A487 road to its west, the A489 road to its south and the A470 road to its east, and has the town of Machynlleth 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, 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 an estimated c 20m of drop, based on the 307m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and an estimated c 287m bwlch height, based on interpolation of 10m contouring between 280m – 290m. 

Extract from the Ordnance Survey 1:25,000 Explorer map

Since the original publication of the Welsh P30 lists on Geoff Crowder’s v-g.me website there have been a number of maps made available online.  Some of these are historic such as the series of Six-Inch maps on the National Library of Scotland website.  Whilst others were digitally updated such as the Ordnance Survey Vector Map Local that was hosted on the Geograph website and which was entitled the Interactive Coverage Map, whilst others are current such as the interactive mapping on the Magic Maps and WalkLakes websites. 

One of the resources recently available online is the mapping on the OS Maps website and the details for this hill were subsequently re-assessed against this mapping.  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 mapping had bwlch contouring between 285m – 290m, with interpolation placing the height of the bwlch as an estimated c 288m, with these contours also represented on other 5m contouring available online. 

Extract from online 5m contouring

Therefore, the deletion of this hill from Sub-Trichant status is due to detail on contemporary maps produced from Ordnance Survey data, resulting in a 307m summit height and an estimated c 288m bwlch height, with these values giving this hill an estimated c 19m of drop, which is insufficient for it to be classified as a Sub-Trichant. 

 

The full details for the hill are: 

Group:  Aran Fawddwy 

Name:  Mynydd Pant Goch 

OS 1:50,000 map:  124

Summit Height:  307m (spot height)                                                           

Summit Grid Reference:  SH 77602 05928 (spot height) 

Bwlch Height:  c 288m (interpolation) 

Bwlch Grid Reference:  SH 77773 05952 (interpolation) 

Drop:  c 19m (spot height summit and interpolated bwlch) 

 

Myrddyn Phillips (February 2022)

 



Mapping Mountains - Hill Reclassifications - Y Trichant

Ffridd Rhyd y Biswail (SH 793 067) – Sub-Trichant addition (135th 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, and the Introduction to the Mapping Mountains publication of the list appearing on the 1st January 2022. 

Y Trichant - The 300m Hills of Wales by Myrddyn Phillips

The name the hill is listed by is Ffridd Rhyd y Biswail, and it is adjoined to the Aran Fawddwy group of hills, which are situated in the south-western part of North Wales (Region A, Sub-Region A3), and it is positioned with the A487 road to its west, the A489 road to its south and the A470 road to its east, and has the town of Machynlleth 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, 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 an estimated c 24m of drop, based on the 312m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and an estimated c 288m bwlch height, based on interpolation of 10m contouring between 280m – 290m. 

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 312m summit height and an estimated c 288m bwlch height, with these values giving this hill an estimated c 24m of drop, which is sufficient for it to be classified as a Sub-Trichant. 

 

The full details for the hill are: 

Group:  Aran Fawddwy 

Name:  Ffridd Rhyd y Biswail 

OS 1:50,000 map:  124

Summit Height:  312m (spot height)                                                           

Summit Grid Reference:  SH 79341 06792 (spot height) 

Bwlch Height:  c 288m (interpolation) 

Bwlch Grid Reference:  SH 79570 06874 (interpolation) 

Drop:  c 24m (spot height summit and interpolated bwlch) 

 

Myrddyn Phillips (February 2022)

 



Mapping Mountains - Hill Reclassifications - Y Trichant


THIS HILL HAS SUBSEQUENTLY BEEN RECLASSIFIED TO SUB-TRICHANT STATUS


Cae Mawr (SN 832 405) – Sub-Trichant reclassified to Trichant (134th reclassification)

Significant Name Changes post for Cae Mawr


There has been a reclassification to the list of Y Trichant – The 300m Hills of Wales, with the summit height, bwlch height and their locations, the drop and status of the hill derived from detail on contemporary maps produced from Ordnance Survey data. 

Partial LIDAR summit coverage of Cae Mawr (SN 832 405)

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, and the Introduction to the Mapping Mountains publication of the list appearing on the 1st January 2022. 

Y Trichant - The 300m Hills of Wales by Myrddyn Phillips

The name the hill is listed by is Cae Mawr and this was derived from the Tithe map, and it is adjoined to the Mynydd Epynt group of hills, which are situated in the central part of South Wales (Region B, Sub-Region B1), and it is positioned with a minor road to its north-west, the A483 road farther to its north-west and the A40 road to its south, and has the town of Llanymddyfri (Llandovery) 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, 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 29m of drop, based on the 313m summit spot height and the 284m bwlch spot height that appear on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map. 

Extract from the Ordnance Survey 1:25,000 Explorer map

Since the original publication of the Welsh P30 lists on Geoff Crowder’s v-g.me website there have been a number of maps made available online.  Some of these are historic such as the series of Six-Inch maps on the National Library of Scotland website.  Whilst others were digitally updated such as the Ordnance Survey Vector Map Local that was hosted on the Geograph website and which was entitled the Interactive Coverage Map, whilst others are current such as the interactive mapping on the Magic Maps and WalkLakes websites. 

One of the resources recently available online is the mapping on the OS Maps website and the details for this hill were subsequently re-assessed against this mapping.  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 mapping had bwlch contouring between 280m – 285m, with interpolation placing the height of the bwlch as an estimated c 283m, with this position favoured over that of the 284m spot height. 

Extract from the OS Maps website

Therefore, the reclassification of this hill from Sub-Trichant status is due to detail on contemporary maps produced from Ordnance Survey data, resulting in a 313m summit height and an estimated c 283m bwlch height, with these values giving this hill an estimated c 30m of drop, which is sufficient for it to be classified as a Trichant. 

 

The full details for the hill are: 

Group:  Mynydd Epynt 

Name:  Cae Mawr 

OS 1:50,000 map:  147, 160

Summit Height:  313m (spot height)                                                           

Summit Grid Reference:  SN 83279 40511 (spot height) 

Bwlch Height:  c 283m (interpolation) 

Bwlch Grid Reference:  SN 83711 41354 (interpolation) 

Drop:  c 30m (spot height summit and interpolated bwlch) 

 

Myrddyn Phillips (February 2022)




Mapping Mountains - Hill Reclassifications - Y Trichant


THIS HILL HAS SUBSEQUENTLY BEEN RECLASSIFIED TO TRICHANT STATUS


Dorth Siwgr (SN 834 427) – Trichant reclassified to Sub-Trichant (133rd reclassification)

Significant Name Changes post for Dorth Siwgr


There has been a reclassification to the list of Y Trichant – The 300m Hills of Wales, with the summit height, bwlch height and their locations, the drop and status of the hill derived from 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, and the Introduction to the Mapping Mountains publication of the list appearing on the 1st January 2022. 

Y Trichant - The 300m Hills of Wales by Myrddyn Phillips

The name the hill is now listed by is Dorth Siwgr and this was derived from online sources, and it is adjoined to the Mynydd Epynt group of hills, which are situated in the central part of South Wales (Region B, Sub-Region B1), and it is positioned with the A483 road to its north-west and a minor road to its south, and has the town of Llanymddyfri (Llandovery) 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, 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 27m of drop, based on an estimated c 323m summit height and an estimated c 296m bwlch height, with both heights based on interpolation of 10m contouring that appear on the Ordnance Survey 1:25,000 Explorer map. 

Extract from the Ordnance Survey 1:25,000 Explorer map

Since the original publication of the Welsh P30 lists on Geoff Crowder’s v-g.me website there have been a number of maps made available online.  Some of these are historic such as the series of Six-Inch maps on the National Library of Scotland website.  Whilst others were digitally updated such as the Ordnance Survey Vector Map Local that was hosted on the Geograph website and which was entitled the Interactive Coverage Map, whilst others are current such as the interactive mapping on the Magic Maps and WalkLakes websites.

The details for this hill were re-assessed when the Ordnance Survey Vector Map Local hosted on the Geograph website and which was entitled the Interactive Coverage Map became available online.  This mapping had many spot heights not on other publicly available Ordnance Survey maps and for this hill it had a 326m summit spot height and when coupled with the c 296m estimated bwlch height; these values gave this hill an estimated c 30m of drop.  The 326m summit spot height also appears on the interactive mapping available on the Magic Maps website. 

Extract from the Magic Maps website

One of the resources recently available online is the mapping on the OS Maps website and the details for this hill were subsequently re-assessed against this mapping.  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 mapping had bwlch contouring between 295m – 300m, with interpolation placing the height of the bwlch as an estimated c 297m.  

Extract from the OS Maps website

Therefore, the reclassification of this hill to Sub-Trichant status is due to detail on contemporary maps produced from Ordnance Survey data, resulting in a 326m summit height and an estimated c 297m bwlch height, with these values giving this hill an estimated c 29m of drop, which is insufficient for it to be classified as a Trichant. 

 

The full details for the hill are: 

Group:  Mynydd Epynt 

Name:  Dorth Siwgr 

OS 1:50,000 map:  147, 160

Summit Height:  326m (spot height)                                                           

Summit Grid Reference:  SN 83481 42793 (hand-held GPS via DoBIH) 

Bwlch Height:  c 297m (interpolation) 

Bwlch Grid Reference:  SN 83712 42859 (interpolation) 

Drop:  c 29m (spot height summit and interpolated bwlch) 

 

Myrddyn Phillips (February 2022)

 



Mapping Mountains - Hill Reclassifications - Y Trichant

Ffridd Maes Mawr (SH 781 091) – Trichant deletion (132nd reclassification)


There has been a deletion based on confirmation of the higher summit position 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 deletion applies to are: 

Y Trichant – The 300m Hills of Wales – Welsh hills at or above 300m and below 400m in height that have 30m minimum drop, with an accompanying sub list entitled the Sub-Trichant, with the criteria for this sub category being all Welsh hills at or above 300m and below 400m in height with 20m or more and below 30m of drop.  The list is authored by Myrddyn Phillips with the Introduction to the list and the renaming of it appearing on Mapping Mountains on the 13th May 2017, and the Introduction to the Mapping Mountains publication of the list appearing on the 1st January 2022. 

Y Trichant - The 300m Hills of Wales by Myrddyn Phillips

The name the hill is listed by is Ffridd Maes Mawr, and it is adjoined to the Aran Fawddwy group of hills, which are situated in the south-western part of North Wales (Region A, Sub-Region A3), and it is positioned with minor roads to its north and west, the A487 road farther to its west and the A470 road to its east, and has the village of Aberllefenni 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 main P30 category with an accompanying note stating; 375m on 1984 1:50,000 map at GR784091, as detail on Ordnance Survey 1:25,000 Explorer maps was prioritised over detail on Ordnance Survey 1:50,000 Landranger maps. 

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 with the summit for the qualifying P30 relocated, resulting in this hill being listed with 15m of drop, based on the 371m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and the 356m 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. 

Extract from the Ordnance Survey 1:50,000 Landranger map

Therefore, the deletion of this hill from Trichant status is due to detail on contemporary maps produced from Ordnance Survey data confirming the adjacent hill positioned at SH 783 090 as higher, resulting in a 371m summit height and a 356m bwlch height, with these values giving this hill 15m of drop, which is insufficient for it to be classified as a Trichant. 

 

The full details for the hill are: 

Group:  Aran Fawddwy 

Name:  Ffridd Maes Mawr 

OS 1:50,000 map:  124

Summit Height:  371m (spot height)                                                           

Summit Grid Reference:  SH 78197 09198 (spot height) 

Bwlch Height:  356m (spot height) 

Bwlch Grid Reference:  SH 78262 09153 (spot height) 

Drop:  15m (spot height summit and bwlch) 

 

Myrddyn Phillips (February 2022)

 



Mapping Mountains - Hill Reclassifications - Y Trichant

Allt Cilhywi (SO 035 358) – Trichant reclassified to Sub-Trichant (131st reclassification)


THIS HILL HAS SUBSEQUENTLY BEEN REINSTATED TO TRICHANT STATUS


There has been a reclassification to the list of Y Trichant – The 300m Hills of Wales, with the summit height, bwlch height and their locations, the drop and status of the hill derived from LIDAR analysis conducted by Myrddyn Phillips. 

LIDAR image of Allt Cilhywi (SO 035 358)

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, and the Introduction to the Mapping Mountains publication of the list appearing on the 1st January 2022. 

Y Trichant - The 300m Hills of Wales by Myrddyn Phillips

The name the hill is listed by is Allt Cilhywi, and it is adjoined to the Mynydd Epynt group of hills, which are situated in the central part of South Wales (Region B, Sub-Region B1), and it is positioned with a minor road to its north and the B4520 road to its west, and has the small community of Lower Chapel 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 included in the Hills to be surveyed sub 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 334m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and an estimated c 304m bwlch height, based on interpolation of 10m contouring between 300m – 310m.  The details for this hill were later re-assessed against the Ordnance Survey 1:25,000 Explorer map and the drop value amended to an estimated c 31m based on an interpolated bwlch height of c 303m. 

Extract from the Ordnance Survey 1:25,000 Explorer map

However, it was not until LIDAR became available that the details for this hill could be accurately re-assessed.  The LIDAR (Light Detection & Ranging) technique produced highly accurate height data that is now freely available for much of England and Wales.  

Therefore, the reclassification of this hill to Sub-Trichant status is due to LIDAR analysis, resulting in a 333.2m summit height and a 303.5m bwlch height, with these values giving this hill 29.7m of drop, which is insufficient for it to be classified as a Trichant. 

 

The full details for the hill are: 

Group:  Mynydd Epynt 

Name:  Allt Cilhywi 

OS 1:50,000 map:  160

Summit Height:  333.2m (LIDAR)                                                           

Summit Grid Reference:  SO 03529 35837 (LIDAR) 

Bwlch Height:  303.5m (LIDAR) 

Bwlch Grid Reference:  SO 03894 35957 (LIDAR) 

Drop:  29.7m (LIDAR) 

 

Myrddyn Phillips (February 2022)

 

 


Mapping Mountains - Hill Reclassifications - Y Trichant

Mynydd Pen Lan (SH 783 090) – Trichant addition (130th reclassification)

Significant Name Changes post for Mynydd Pen Lan


There has been an addition based on confirmation of the higher summit position 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, and the Introduction to the Mapping Mountains publication of the list appearing on the 1st January 2022. 

Y Trichant - The 300m Hills of Wales by Myrddyn Phillips

The name the hill is listed by is Mynydd Pen Lan, and it is adjoined to the Aran Fawddwy group of hills, which are situated in the south-western part of North Wales (Region A, Sub-Region A3), and it is positioned with minor roads to its north and west, the A487 road farther to its west and the A470 road to its east, and has the village of Aberllefenni 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 main P30 category, with the prioritised P30 status allocated to the 371m map heighted hill positioned at SH 781 091 with an accompanying note stating; 375m on 1984 1:50,000 map at GR784091. 

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 with the prioritised summit relocated and it was listed with an estimated c 39m of drop, based on the 375m summit spot height that appears on the Ordnance Survey 1:50,000 Landranger map and an estimated c 336m bwlch height, based on interpolation of 10m contouring between 330m – 340m that appear on the Ordnance Survey 1:25,000 Explorer map. 

Extract from the Ordnance Survey 1:50,000 Landranger map

Since the original publication of the Welsh P30 lists on Geoff Crowder’s v-g.me website there have been a number of maps made available online.  Some of these are historic such as the series of Six-Inch maps on the National Library of Scotland website.  Whilst others were digitally updated such as the Ordnance Survey Vector Map Local that was hosted on the Geograph website and which was entitled the Interactive Coverage Map, whilst others are current such as the interactive mapping on the Magic Maps and WalkLakes websites. 

One of the resources recently available online is the mapping on the OS Maps website and the details for this hill were subsequently re-assessed against this mapping.  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 mapping had bwlch contouring between 335m – 340m, with interpolation placing the height of the bwlch as an estimated c 338m. 

Therefore, the addition of this hill to Trichant status is due to detail on contemporary maps produced from Ordnance Survey data confirming the adjacent hill positioned at SH 781 091 as lower, resulting in a 375m summit height and an estimated c 338m bwlch height, with these values giving this hill an estimated c 37m of drop, which is sufficient for it to be classified as a Trichant. 

 

The full details for the hill are: 

Group:  Aran Fawddwy 

Name:  Mynydd Pen Lan 

OS 1:50,000 map:  124

Summit Height:  375m (spot height)                                                           

Summit Grid Reference:  SH 78343 09027 (hand-held GPS via DoBIH) 

Bwlch Height:  c 338m (interpolation) 

Bwlch Grid Reference:  SH 78157 08694 (interpolation) 

Drop:  c 37m (spot height summit and interpolated bwlch) 

 

Myrddyn Phillips (February 2022)




Mapping Mountains - Hill Reclassifications - Y Trichant

Y Lan Fach Bwlch (SN 836 424) – Sub-Trichant reclassified to Trichant (129th reclassification)

Significant Name Changes post for Y Lan Fach Bwlch


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, and the Introduction to the Mapping Mountains publication of the list appearing on the 1st January 2022. 

Y Trichant - The 300m Hills of Wales by Myrddyn Phillips

The name the hill is listed by is Y Lan Fach Bwlch and this was derived from the Tithe map, and it is adjoined to the Mynydd Epynt group of hills, which are situated in the central part of South Wales (Region B, Sub-Region B1), and it is positioned with the A483 road to its north-west and a minor road to its south, and has the town of Llanymddyfri (Llandovery) 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, 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 31m of drop, based on the 335m summit spot height that appears on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map and an estimated c 304m bwlch height, based on interpolation of 10m contouring between 300m – 310m.  The details for this hill were later re-assessed against the Ordnance Survey 1:25,000 Explorer map and its drop value amended to an estimated c 32m based on an interpolated bwlch height of c 303m. 

Extract from the Ordnance Survey 1:25,000 Explorer map

Since the original publication of the Welsh P30 lists on Geoff Crowder’s v-g.me website there have been a number of maps made available online.  Some of these are historic such as the series of Six-Inch maps on the National Library of Scotland website.  Whilst others were digitally updated such as the Ordnance Survey Vector Map Local that was hosted on the Geograph website and which was entitled the Interactive Coverage Map, whilst others are current such as the interactive mapping on the Magic Maps and WalkLakes websites. 

One of the resources recently available online is the mapping on the OS Maps website and the details for this hill were subsequently re-assessed against this mapping.  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 mapping had bwlch contouring between 300m – 305m, with interpolation placing the height of the bwlch as an estimated c 302m. 

Therefore, the confirmation of the reclassification of this hill from Sub-Trichant status is due to detail on contemporary maps produced from Ordnance Survey data, resulting in a 335m summit height and an estimated c 302m bwlch height, with these values giving this hill an estimated c 33m of drop, which is sufficient for it to be classified as a Trichant. 

 

The full details for the hill are: 

Group:  Mynydd Epynt 

Name:  Y Lan Fach Bwlch 

OS 1:50,000 map:  147, 160

Summit Height:  335m (spot height)                                                           

Summit Grid Reference:  SN 83616 42481 (hand-held GPS via DoBIH) 

Bwlch Height:  c 302m (interpolation) 

Bwlch Grid Reference:  SN 83714 42683 (interpolation) 

Drop:  c 33m (spot height summit and interpolated bwlch) 

 

Myrddyn Phillips (February 2022)




Mapping Mountains - Hill Reclassifications - Y Trichant

Mynydd Pen Lan (SH 792 088) – Sub-Trichant addition (128th reclassifcation)


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, and the Introduction to the Mapping Mountains publication of the list appearing on the 1st January 2022. 

Y Trichant - The 300m Hills of Wales by Myrddyn Phillips

The name the hill is listed by is Mynydd Pen Lan, and it is adjoined to the Aran Fawddwy group of hills, which are situated in the south-western part of North Wales (Region A, Sub-Region A3), and it is positioned with minor roads to its north and west, the A487 road farther to its west and the A470 road to its east, and has the village of Aberllefenni 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, 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 an estimated c 22m of drop, based on an estimated c 385m summit height and an estimated c 363m bwlch height, with both heights based on interpolation of 10m contouring that appear on the Ordnance Survey 1:25,000 Explorer map. 

Extract from the Ordnance Survey 1:25,000 Explorer map

Since the original publication of the Welsh P30 lists on Geoff Crowder’s v-g.me website there have been a number of maps made available online.  Some of these are historic such as the series of Six-Inch maps on the National Library of Scotland website.  Whilst others were digitally updated such as the Ordnance Survey Vector Map Local that was hosted on the Geograph website and which was entitled the Interactive Coverage Map, whilst others are current such as the interactive mapping on the Magic Maps and WalkLakes websites. 

One of the mapping resources now available online is the Magic Maps website which hosts an interactive map originated from Ordnance Survey data.  This mapping has many spot heights not on other publicly available maps and for this hill it has a 385m summit spot height. 

Extract from the Magic Maps website

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 385m summit height and an estimated c 363m 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:  Aran Fawddwy 

Name:  Mynydd Pen Lan 

OS 1:50,000 map:  124

Summit Height:  385m (spot height)                                                           

Summit Grid Reference:  SH 79211 08819 (spot height) 

Bwlch Height:  c 363m (interpolation) 

Bwlch Grid Reference:  SH 79419 09121 (interpolation) 

Drop:  c 22m (spot height summit and interpolated bwlch) 

 

Myrddyn Phillips (February 2022)

 



Mapping Mountains - Hill Reclassifications - Y Trichant

Mynydd Du (SH 805 084) – Sub-Trichant addition (127th reclassification)

Summit Relocations post for Mynydd Du


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 LIDAR analysis conducted by Myrddyn Phillips. 

LIDAR image of Mynydd Du (SH 805 084)

The criteria for the list that this addition applies to are: 

Y Trichant – The 300m Hills of Wales – Welsh hills at or above 300m and below 400m in height that have 30m minimum drop, with an accompanying sub list entitled the Sub-Trichant, with the criteria for this sub category being all Welsh hills at or above 300m and below 400m in height with 20m or more and below 30m of drop.  The list is authored by Myrddyn Phillips with the Introduction to the list and the renaming of it appearing on Mapping Mountains on the 13th May 2017, and the Introduction to the Mapping Mountains publication of the list appearing on the 1st January 2022. 

Y Trichant - The 300m Hills of Wales by Myrddyn Phillips

The name the hill is listed by is Mynydd Du, and it is adjoined to the Aran Fawddwy group of hills, which are situated in the south-western part of North Wales (Region A, Sub-Region A3), and it is positioned with minor roads to its north and south, the A487 road to its west and the A470 road to its east, and has the village of Aberllefenni 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, 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 and it was listed with 19m of drop, based on the 335m summit spot height that appears on the Ordnance Survey 1:50,000 Landranger map and the 316m 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. 

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 addition of this hill to Sub-Trichant status is due to LIDAR analysis, resulting in a 335.8m summit height and a 314.9m bwlch height, with these values giving this hill 20.9m of drop, which is sufficient for it to be classified as a Trichant. 

 

The full details for the hill are: 

Group:  Aran Fawddwy 

Name:  Mynydd Du 

OS 1:50,000 map:  124, 125

Summit Height:  335.8m (LIDAR)                                                           

Summit Grid Reference:  SH 80572 08424 (LIDAR) 

Bwlch Height:  314.9m (LIDAR) 

Bwlch Grid Reference:  SH 80738 08624 (LIDAR) 

Drop:  20.9m (LIDAR) 

 

Myrddyn Phillips (February 2022)

 



Mapping Mountains - Hill Reclassifications - Y Trichant

Pt. 387.9m (SN 854 382) – Sub-Trichant reclassified to Trichant (126th reclassification)

Significant Name Changes post for Pt. 387.9m


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 and subsequent LIDAR analysis conducted by Myrddyn Phillips. 

LIDAR image of Pt. 387.9m (SN 854 382)

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, and the Introduction to the Mapping Mountains publication of the list appearing on the 1st January 2022. 

Y Trichant - The 300m Hills of Wales by Myrddyn Phillips


The hill is listed by the Point (Pt. 387m) notation as an appropriate name for it either from historic research or local enquiry has not been found, and it is adjoined to the Mynydd Epynt group of hills, which are situated in the central part of South Wales (Region B, Sub-Region B1), and it is positioned with minor roads to its south south-west and east, the A483 road to its west and the A40 road to its south, and has the town of Llanymddyfri (Llandovery) 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 Hills to be surveyed sub 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 32m of drop, based on the 387m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and an estimated c 355m bwlch height, based on interpolation of 10m contouring between 350m – 360m. 

Extract from the Ordnance Survey 1:25,000 Explorer map


Since the original publication of the Welsh P30 lists on Geoff Crowder’s v-g.me website there have been a number of maps made available online.  Some of these are historic such as the series of Six-Inch maps on the National Library of Scotland website.  Whilst others were digitally updated such as the Ordnance Survey Vector Map Local that was hosted on the Geograph website and which was entitled the Interactive Coverage Map, whilst others are current such as the interactive mapping on the Magic Maps and WalkLakes websites. 

The details for this hill were re-assessed when the Ordnance Survey Vector Map Local hosted on the Geograph website and which was entitled the Interactive Coverage Map became available online.  This mapping had many spot heights not on other publicly available Ordnance Survey maps and for this hill it had a 355m spot height on the area of the bwlch. 

One of the resources recently available online is the mapping on the OS Maps website and the details for this hill were subsequently re-assessed against this mapping.  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 mapping had bwlch contouring between 355m – 360m, with interpolation placing the height of the bwlch as an estimated c 357m, which is being prioritised compared to the positioning of the 355m spot height at SN 85558 38402. 

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 confirmation of the reclassification of this hill from Sub-Trichant status is due to LIDAR analysis, resulting in a 387.9m summit height and a 356.1m bwlch height, with these values giving this hill 31.7m of drop, which is sufficient for it to be classified as a Trichant. 

 

The full details for the hill are: 

Group:  Mynydd Epynt 

Name:  Pt. 387.9m 

OS 1:50,000 map:  160

Summit Height:  387.9m (LIDAR)                                                           

Summit Grid Reference:  SN 85493 38202 (LIDAR) 

Bwlch Height:  356.1m (LIDAR) 

Bwlch Grid Reference:  SN 85555 38424 (LIDAR) 

Drop:  31.7m (LIDAR) 

 

Myrddyn Phillips (February 2022)





Mapping Mountains - Hill Reclassifications - Y Trichant

Mynydd Esgairneiriau (SH 789 093) – Sub-Trichant addition (125th 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. 

Mynydd Esgairneiriau (SH 789 093)

The criteria for the list that this addition applies to are: 

Y Trichant – The 300m Hills of Wales – Welsh hills at or above 300m and below 400m in height that have 30m minimum drop, with an accompanying sub list entitled the Sub-Trichant, with the criteria for this sub category being all Welsh hills at or above 300m and below 400m in height with 20m or more and below 30m of drop.  The list is authored by Myrddyn Phillips with the Introduction to the list and the renaming of it appearing on Mapping Mountains on the 13th May 2017, and the Introduction to the Mapping Mountains publication of the list appearing on the 1st January 2022. 

Y Trichant - The 300m Hills of Wales by Myrddyn Phillips

The name the hill is listed by is Mynydd Esgairneiriau, and it is adjoined to the Aran Fawddwy group of hills, which are situated in the south-western part of North Wales (Region A, Sub-Region A3), and it is positioned with minor roads to its north and west, the A487 road farther to its west and the A470 road farther to its east, and has the village of Aberllefenni 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, 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 and it was listed with 22m of drop, based on the 355m summit spot height that appears on the Ordnance Survey 1:50,000 Landranger map and the 333m 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. 

Extract from the Ordnance Survey 1:50,000 Landranger 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 355m summit height and a 333m bwlch height, with these values giving this hill 22m of drop, which is sufficient for it to be classified as a Sub-Trichant.

 

The full details for the hill are: 

Group:  Aran Fawddwy 

Name:  Mynydd Esgairneiriau 

OS 1:50,000 map:  124

Summit Height:  355m (spot height)                                                           

Summit Grid Reference:  SH 78959 09392 (spot height) 

Bwlch Height:  333m (spot height) 

Bwlch Grid Reference:  SH 79125 09370 (spot height) 

Drop:  22m (spot height summit and bwlch) 

 

Myrddyn Phillips (February 2022)




Mapping Mountains - Hill Reclassifications - Y Trichant

Y Grug (SH 809 103) – Sub-Trichant addition (124th 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, and the Introduction to the Mapping Mountains publication of the list appearing on the 1st January 2022. 

Y Trichant - The 300m Hills of Wales by Myrddyn Phillips

The name the hill is listed by is Y Grug, and it is adjoined to the Aran Fawddwy group of hills, which are situated in the south-western part of North Wales (Region A, Sub-Region A3), and it is positioned with the A470 road to its east and north, the A487 road to its west and a minor road to its north, and has the small town of Dinas Mawddwy 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, 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 18m of drop, based on the 376m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and the 358m bwlch spot height positioned at SH 80775 10135 that appeared on the Ordnance Survey Vector Map Local hosted on the Geograph website and which was entitled the Interactive Coverage Map. 

Extract from the Ordnance Survey 1:25,000 Explorer map

Since the original publication of the Welsh P30 lists on Geoff Crowder’s v-g.me website there have been a number of maps made available online.  Some of these are historic such as the series of Six-Inch maps on the National Library of Scotland website.  Whilst others were digitally updated such as the Ordnance Survey Vector Map Local that was hosted on the Geograph website and which was entitled the Interactive Coverage Map, whilst others are current such as the interactive mapping on the Magic Maps and WalkLakes websites. 

One of the resources recently available online is the mapping on the OS Maps website and the details for this hill were subsequently re-assessed against this mapping.  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 mapping had bwlch contouring between 355m – 360m; with interpolation placing the height of the bwlch as an estimated c 356m and this position is favoured over that of the 358m spot height. 

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 376m summit height and an estimated c 356m bwlch height, with these values giving this hill an estimated c 20m of drop, which is sufficient for it to be classified as a Sub-Trichant. 

 

The full details for the hill are: 

Group:  Aran Fawddwy 

Name:  Y Grug 

OS 1:50,000 map:  124, 125

Summit Height:  376m (spot height)                                                           

Summit Grid Reference:  SH 80961 10323 (spot height) 

Bwlch Height:  c 356m (interpolation) 

Bwlch Grid Reference:  SH 80813 10183 (interpolation) 

Drop:  c 20m (spot height summit and interpolated bwlch) 

 

Myrddyn Phillips (January 2022)




Mapping Mountains - Hill Reclassifications - Y Trichant

Mynydd Cwm Gerwyn (SH 806 109) – Sub-Trichant deletion (123rd reclassification)


There has been a deletion 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 deletion applies to are: 

Y Trichant – The 300m Hills of Wales – Welsh hills at or above 300m and below 400m in height that have 30m minimum drop, with an accompanying sub list entitled the Sub-Trichant, with the criteria for this sub category being all Welsh hills at or above 300m and below 400m in height with 20m or more and below 30m of drop.  The list is authored by Myrddyn Phillips with the Introduction to the list and the renaming of it appearing on Mapping Mountains on the 13th May 2017, and the Introduction to the Mapping Mountains publication of the list appearing on the 1st January 2022. 

Y Trichant  The 300m Hills of Wales by Myrddyn Phillips

The name the hill is listed by is Mynydd Cwm Gerwyn, and it is adjoined to the Aran Fawddwy group of hills, which are situated in the south-western part of North Wales (Region A, Sub-Region A3), and it is positioned with the A470 road to its east and north, the A487 road to its west and a minor road to its south, and has the small town of Dinas Mawddwy 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, 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 an estimated c 20m of drop, based on the 333m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and an estimated c 313m bwlch height based on interpolation of 10m contouring between 310m – 320m. 

Extract from the Ordnance Survey 1:25,000 Explorer map

Since the original publication of the Welsh P30 lists on Geoff Crowder’s v-g.me website there have been a number of maps made available online.  Some of these are historic such as the series of Six-Inch maps on the National Library of Scotland website.  Whilst others were digitally updated such as the Ordnance Survey Vector Map Local that was hosted on the Geograph website and which was entitled the Interactive Coverage Map, whilst others are current such as the interactive mapping on the Magic Maps and WalkLakes websites. 

One of the resources recently available online is the mapping on the OS Maps website and the details for this hill were subsequently re-assessed against this mapping.  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 mapping had bwlch contouring between 315m – 320m, with interpolation placing the height of the bwlch as an estimated c 316m. 

Therefore, the deletion of this hill from Sub-Trichant status is due to detail on contemporary maps produced from Ordnance Survey data, resulting in a 333m summit height and an estimated c 316m bwlch height, with these values giving this hill an estimated c 17m of drop, which is insufficient for it to be classified as a Sub-Trichant. 

 

The full details for the hill are: 

Group:  Aran Fawddwy 

Name:  Mynydd Cwm Gerwyn 

OS 1:50,000 map:  124, 125

Summit Height:  333m (spot height)                                                           

Summit Grid Reference:  SH 80690 10901 (spot height) 

Bwlch Height:  c 316m (interpolation) 

Bwlch Grid Reference:  SH 80660 11132 (interpolation) 

Drop:  c 17m (spot height summit and interpolated bwlch) 

 

Myrddyn Phillips (January 2022)




Mapping Mountains - Hill Reclassifications - Y Trichant

Mynydd Hendre Ddu (SH 796 120) – Sub-Trichant addition (122nd 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, and the Introduction to the Mapping Mountains publication of the list appearing on the 1st January 2022. 

Y Trichant - The 300m Hills of Wales by Myrddyn Phillips

The name the hill is listed by is Mynydd Hendre Ddu, and it is adjoined to the Aran Fawddwy group of hills, which are situated in the south-western part of North Wales (Region A, Sub-Region A3), and it is positioned with the A470 road to its north-east, the A487 road to its west and a minor road to its south, and has the small town of Dinas Mawddwy 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, 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 24m of drop, based on the 393m summit spot height and the 369m bwlch spot height that appear on the Ordnance Survey 1:25,000 Explorer map. 

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 393m summit height and a 369m bwlch height, with these values giving this hill 24m of drop, which is sufficient for it to be classified as a Sub-Trichant. 

 

The full details for the hill are: 

Group:  Aran Fawddwy 

Name:  Mynydd Hendre Ddu 

OS 1:50,000 map:  124

Summit Height:  393m (spot height)                                                           

Summit Grid Reference:  SH 79627 12091 (spot height) 

Bwlch Height:  369m (spot height) 

Bwlch Grid Reference:  SH 79464 12271 (spot height) 

Drop:  24m (spot height summit and bwlch) 

 

Myrddyn Phillips (January 2022)




Mapping Mountains - Hill Reclassifications - Y Trichant

Pt. 303.45m (SH 874 163) – Sub-Trichant reclassified to Trichant (121st reclassification)

Significant Name Changes post for Pt. 303.45m


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 LIDAR analysis conducted by Myrddyn Phillips. 

LIDAR image of Pt. 303.45m (SH 874 163)

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, and the Introduction to the Mapping Mountains publication of the list appearing on the 1st January 2022. 

Y Trichant - The 300m Hills of Wales by Myrddyn Phillips

The hill is listed by the Point (Pt. 303.45m) notation as an appropriate name for it either from historic research or local enquiry has not been found, and it is adjoined to the Aran Fawddwy group of hills, which are situated in the south-western part of North Wales (Region A, Sub-Region A3), and it is positioned with minor roads to its west and south, and the A470 road farther to its south-west, and has the small town of Dinas Mawddwy 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, as it was considered not to meet the criteria then used for the main P30 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 an estimated c 27m of drop, based on the 304m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and an estimated c 277m bwlch height, 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 against Harvey Map data using the 1:40,000 Snowdonia South British Mountain Map.  This mapping has many spot heights not on other publicly available maps and for this hill is has a 304m summit spot height and a 269m bwlch spot height, with these values giving this hill 35m of drop. 

Extract from the Harvey 1:40,000 Snowdonia South British Mountain Map

The details for this hill were re-assessed when the Ordnance Survey Vector Map Local hosted on the Geograph website and which was entitled the Interactive Coverage Map became available online.  This mapping had many spot heights not on other publicly available Ordnance Survey maps and for this hill it had a 272m bwlch spot height which was prioritised over the Harvey Map data, and when coupled with the 304m summit spot height, these values give this hill 32m 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 confirmation of the reclassification of this hill from Sub-Trichant status is due to LIDAR analysis, resulting in a 303.45m summit height and a 271.1m bwlch height, with these values giving this hill 32.4m of drop, which is sufficient for it to be classified as a Trichant. 

 

The full details for the hill are: 

Group:  Aran Fawddwy 

Name:  Pt. 303.45m 

OS 1:50,000 map:  124, 125

Summit Height:  303.45m (LIDAR)                                                           

Summit Grid Reference:  SH 87457 16343 (LIDAR) 

Bwlch Height:  271.1m (LIDAR) 

Bwlch Grid Reference:  SH 87614 16397 (LIDAR) 

Drop:  32.4m (LIDAR) 

 

Myrddyn Phillips (January 2022)




Mapping Mountains - Hill Reclassifications - Y Trichant

Foel Ispri (SH 702 201) – Sub-Trichant addition (120th 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 and LIDAR analysis conducted by Myrddyn Phillips. 

LIDAR summit image of Foel Ispri (SH 702 201)

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. 

Y Trichant - The 300m Hills of Wales by Myrddyn Phillips

The name the hill is listed by is Foel Ispri, and it is adjoined to the Y Llethr group of hills, which are situated in the western part of North Wales (Region A, Sub-Region A2), and it is positioned with minor roads to its west and east, the A496 road to its south and the A470 road farther to its east, and has the village of Llanelltyd 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, 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 an estimated c 22m of drop, based on the 328m 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 306m based on interpolation of 10m contouring between 300m – 310m. 

Extract from the Ordnance Survey 1:25,000 Explorer map

Since the publication of the Welsh P30 lists on Geoff Crowder’s v-g.me website there have been a number of maps made available online.  Some of these are historic such as the series of Six-Inch maps on the National Library of Scotland website.  Whilst others were digitally updated such as the Ordnance Survey Vector Map Local that was hosted on the Geograph website and which was entitled the Interactive Coverage Map, whilst others are current such as the interactive mapping on the Magic Maps and WalkLakes websites. 

The details for this hill were re-evaluated when the Ordnance Survey Vector Map Local hosted on the Geograph website and which was entitled the Interactive Coverage Map became available online.  This mapping had many spot heights not on other publicly available maps and for this hill it had a 327m summit spot height, resulting in the drop value being amended to an estimated c 21m. 

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 detail on contemporary maps produced from Ordnance Survey data and LIDAR analysis, resulting in a 327.4m summit height and an estimated c 306m 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:  Y Llethr 

Name:  Foel Ispri 

OS 1:50,000 map:  124

Summit Height:  327.4m (LIDAR)                                                           

Summit Grid Reference:  SH 70244 20174 (LIDAR) 

Bwlch Height:  c 306m (interpolation) 

Bwlch Grid Reference:  SH 70216 20385 (interpolation) 

Drop:  c 21m (LIDAR summit and interpolated bwlch) 

 

Myrddyn Phillips (January 2022)

 



Mapping Mountains - Hill Reclassifications - Y Trichant

Mynydd Glan Llyn y Forwyn (SH 686 238) – Sub-Trichant addition (119th 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. 

Y Trichant - The 300m Hills of Wales by Myrddyn Phillips

The name the hill is listed by is Mynydd Glan Llyn y Forwyn, and it is adjoined to the Y Llethr group of hills, which are situated in the western part of North Wales (Region A, Sub-Region A2), and it is positioned with the A496 road to its south and the A470 road to its east, and has the village of Ganllwyd 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, as it was considered not to meet the criteria then used for this sub category, with the caveat that its twin 378m map heighted summit positioned at SH 68596 23970 was given priority summit status, with an accompanying note stating; Two points of same height – other at SH687238. 

After the sub list was standardised, and interpolated heights and drop values also included the details for this hill were re-evaluated and it was listed with an estimated c 21m of drop, based on the 378m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and an estimated bwlch height of c 357m based on interpolation of 10m contouring between 350m – 360m. 

Extract from the Ordnance Survey 1:25,000 Explorer map

Since the original publication of the Welsh P30 lists on Geoff Crowder’s v-g.me website there have been a number of maps made available online.  Some of these are historic such as the series of Six-Inch maps on the National Library of Scotland website.  Whilst others were digitally updated such as the Ordnance Survey Vector Map Local that was hosted on the Geograph website and which was entitled the Interactive Coverage Map, whilst others are current such as the interactive mapping on the Magic Maps and WalkLakes websites. 

One of the resources recently available online is the mapping on the OS Maps website and the details for this hill were subsequently re-assessed against this mapping.  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 mapping had bwlch contouring between 355m – 360m, with interpolation placing the height of the bwlch as an estimated c 356m. 

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 378m summit height and an estimated c 356m 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:  Y Llethr 

Name:  Mynydd Glan Llyn y Forwyn 

OS 1:50,000 map:  124

Summit Height:  378m (spot height)                                                           

Summit Grid Reference:  SH 68660 23806 (hand-held GPS via DoBIH) 

Bwlch Height:  c 356m (interpolation) 

Bwlch Grid Reference:  SH 68637 23856 (interpolation) 

Drop:  c 22m (spot height summit and interpolated bwlch) 

 

Myrddyn Phillips (January 2022)




Mapping Mountains - Hill Reclassifications - Y Trichant

Mynydd Glan Llyn y Forwyn (SH 685 239) – Sub-Trichant reclassified to Trichant (118th reclassification)


There has been a reclassification to the list of Y Trichant – The 300m Hills of Wales, with the summit height, bwlch height and their locations, the drop and status of the hill derived from 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. 

Y Trichant - The 300m Hills of Wales by Myrddyn Phillips

The name the hill is listed by is Mynydd Glan Llyn y Forwyn, and it is adjoined to the Y Llethr group of hills, which are situated in the western part of North Wales (Region A, Sub-Region A2), and it is positioned with the A496 road to its south and the A470 road to its east, and has the village of Ganllwyd 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 included in the Hills to be surveyed sub list, as it was considered not to meet the criteria then used for the main P30 category, with an accompanying note stating; Two points of same height – other at SH687238. 

Extract from the Ordnance Survey 1:25,000 Explorer map

Since the original publication of the Welsh P30 lists on Geoff Crowder’s v-g.me website there have been a number of maps made available online.  Some of these are historic such as the series of Six-Inch maps on the National Library of Scotland website.  Whilst others were digitally updated such as the Ordnance Survey Vector Map Local that was hosted on the Geograph website and which was entitled the Interactive Coverage Map, whilst others are current such as the interactive mapping on the Magic Maps and WalkLakes websites. 

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 on other publicly available maps and for this hill it had a 343m bwlch spot height and when coupled with the 378m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map, these values give this hill 35m of drop.

Therefore, the reclassification of this hill from Sub-Trichant status is due to detail on contemporary maps produced from Ordnance Survey data, resulting in a 378m summit height and a 343m bwlch height, with these values giving this hill 35m of drop, which is sufficient for it to be classified as a Trichant. 

 

The full details for the hill are: 

Group:  Y Llethr 

Name:  Mynydd Glan Llyn y Forwyn 

OS 1:50,000 map:  124

Summit Height:  378m (spot height)                                                           

Summit Grid Reference:  SH 68596 23970 (hand-held GPS via DoBIH) 

Bwlch Height:  343m (spot height) 

Bwlch Grid Reference:  SH 68817 23700 (spot height) 

Drop:  35m (spot height summit and bwlch) 

 

Myrddyn Phillips (January 2022)

 



Mapping Mountains - Hill Reclassifications - Y Trichant

Pt. 341.7m (SH 991 387) – Sub-Trichant addition (117th 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 LIDAR analysis conducted by Myrddyn Phillips. 

LIDAR image of Pt. 341.7m (SH 991 387)

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. 

Y Trichant - The 300m Hills of Wales by Myrddyn Phillips

The hill is listed by the Point (Pt. 341.7m) notation as an appropriate name for it either from historic research or local enquiry has not been found, and it is adjoined to the Carnedd y Filiast group of hills, which are situated in the central part of North Wales (Region A, Sub-Region A2), and it is positioned with the B4402 and A494 roads to its north-west and a minor road to its south-east, and has the town of Y Bala 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 not included in the Hills to be surveyed sub 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 an estimated c 22m of drop, based on the 343m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and an estimated c 321m bwlch height, based on interpolation of 10m contouring between 320m – 330m that appears on the Ordnance Survey 1:25,000 Explorer map. 

Extract from the Ordnance Survey 1:25,000 Explorer map

However, it was not until LIDAR became available that the details for this hill could be accurately re-assessed.  The LIDAR (Light Detection & Ranging) technique produced highly accurate height data that is now freely available for much of England and Wales. 

Therefore, the confirmation of the addition of this hill to Sub-Trichant status is due to LIDAR analysis, resulting in a 341.7m summit height and a 319.8m bwlch height, with these values giving this hill 21.9m of drop, which is sufficient for it to be classified as a Sub-Trichant. 

 

The full details for the hill are: 

Group:  Carnedd y Filiast 

Name:  Pt. 341.7m 

OS 1:50,000 map:  125

Summit Height:  341.7m (LIDAR)                                                           

Summit Grid Reference:  SH 99160 38743 & SH 99149 38733 (LIDAR) 

Bwlch Height:  319.8m (LIDAR) 

Bwlch Grid Reference:  SH 99178 39080 (LIDAR) 

Drop:  21.9m (LIDAR) 

 

Myrddyn Phillips (January 2022)




Mapping Mountains - Hill Reclassifications - Y Trichant

Moel Goedog (SH 615 324) – Sub-Trichant addition (116th 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. 

Y Trichant - The 300m Hills of Wales by Myrddyn Phillips

The name the hill is listed by is Moel Goedog, and it is adjoined to the Y Llethr group of hills, which are situated in the western part of North Wales (Region A, Sub-Region A2), and it is positioned with a minor road to its west and south, the B4573 road and the A496 road farther to its west, and has the village of Harlech 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 not included in the Hills to be surveyed sub 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

Since the original publication of the Welsh P30 lists on Geoff Crowder’s v-g.me website there have been a number of maps made available online.  Some of these are historic such as the series of Six-Inch maps on the National Library of Scotland website.  Whilst others were digitally updated such as the Ordnance Survey Vector Map Local that was hosted on the Geograph website and which was entitled the Interactive Coverage Map, whilst others are current such as the interactive mapping on the Magic Maps and WalkLakes websites. 

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 on other publicly available maps and for this hill it had a 378m summit spot height and a 358m bwlch spot height, with these values giving this hill 20m of drop. 

Extract from the WalkLakes website

One of the mapping resources 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 the 378m spot height is also given on the summit area of this hill. 

Another of the mapping resources now available online is the Magic Maps website which hosts an interactive map originated from Ordnance Survey data.  This mapping also shows a 378m spot height on the summit area of this hill. 

Extract from the Magic Maps website

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 378m summit height and a 358m 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:  Y Llethr 

Name:  Moel Goedog 

OS 1:50,000 map:  124

Summit Height:  378m (spot height)                                                           

Summit Grid Reference:  SH 61591 32452 (spot height) 

Bwlch Height:  358m (spot height) 

Bwlch Grid Reference:  SH 61685 32485 (spot height) 

Drop:  20m (spot height summit and bwlch) 

 

Myrddyn Phillips (January 2022)

 



Mapping Mountains - Hill Reclassifications - Y Trichant

Pt. 385m (SH 627 326) – Sub-Trichant reclassified to Trichant (115th reclassification)

Significant Name Changes post for Pt. 385m


There has been a reclassification to the list of Y Trichant – The 300m Hills of Wales, with the summit height, bwlch height and their locations, the drop and status of the hill derived from 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, and the Introduction to the Mapping Mountains publication of the list appearing on the 1st January 2022. 

Y Trichant - The 300m Hills of Wales by Myrddyn Phillips

The hill is being listed by the point (Pt. 385m) 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 Y Llethr group of hills, which are situated in the western part of North Wales (Region A, Sub-Region A2), and it is positioned with minor roads to its west and south, and the B4573 road and the A496 road farther to its west, and has the village of Harlech 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 Hills to be surveyed sub list, as it was considered not to meet the criteria then used for the main P30 category. 

Extract from the Harvey 1:25,000 Superwalker map to the Rhinogydd

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 35m of drop, based on the 386m summit spot height that appears on the Harvey 1:25,000 Superwalker map to the Rhinogydd and an estimated c 351m bwlch height, based on interpolation of 10m contouring between 350m – 360m that appear on the Ordnance Survey 1:25,000 Explorer map. 

Extract from the Ordnance Survey 1:25,000 Explorer map

The details for this hill were subsequently re-assessed when the Ordnance Survey Vector Map Local hosted on the Geograph website and which was entitled the Interactive Coverage Map became available online.  This mapping had many spot heights not on other publicly available maps and for this hill it had a 385m summit spot height and a 351m bwlch spot height.  This re-assessment resulted in the drop value being amended to 34m. 

Therefore, the reclassification of this hill from Sub-Trichant status is due to detail on contemporary maps produced from Ordnance Survey data, resulting in a 385m summit height and a 351m bwlch height, with these values giving this hill 34m of drop, which is sufficient for it to be classified as a Trichant. 

 

The full details for the hill are: 

Group:  Y Llethr 

Name:  Pt. 385m 

OS 1:50,000 map:  124

Summit Height:  385m (spot height)                                                           

Summit Grid Reference:  SH 62790 32628 (hand-held GPS via DoBIH) 

Bwlch Height:  351m (spot height) 

Bwlch Grid Reference:  SH 62933 33128 (spot height) 

Drop:  34m (spot height summit and bwlch) 

 

Myrddyn Phillips (January 2022)

 

 


Mapping Mountains - Hill Reclassifications - Y Trichant

Y Gyrn (SH 641 359) – Sub-Trichant addition (114th 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. 

Y Trichant - The 300m Hills of Wales by Myrddyn Phillips

The name the hill is listed by is Y Gyrn, and it is adjoined to the Rhinogydd group of hills, which are situated in the western part of North Wales (Region A, Sub-Region A3), and it is positioned with a minor road to its north-west and the A496 road to its west, and has the village of Harlech 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, 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 349m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and an estimated c 328m bwlch height, based on interpolation of 10m contouring between 320m – 330m that appear on the Ordnance Survey 1:25,000 Explorer map. 

Extract from the Ordnance Survey 1:25,000 Explorer map

The details for this hill were subsequently 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 mapping had bwlch contouring between 325m – 330m, with interpolation giving an estimated bwlch height of c 327m.  This re-assessment resulted in the drop value being amended to an estimated c 22m. 

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 349m summit height and an estimated c 327m 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:  Rhinogydd 

Name:  Y Gyrn 

OS 1:50,000 map:  124

Summit Height:  349m (spot height)                                                           

Summit Grid Reference:  SH 64172 35969 (spot height) 

Bwlch Height:  c 327m (interpolation) 

Bwlch Grid Reference:  SH 64353 35812 (interpolation) 

Drop:  c 22m (spot height summit and interpolated bwlch) 

 

Myrddyn Phillips (December 2021)




Mapping Mountains - Hill Reclassifications - Y Trichant

Moel Caws (SH 846 278) – Sub-Trichant addition (113th 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 LIDAR analysis conducted by Myrddyn Phillips. 

LIDAR image of Moel Caws (SH 846 278)

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. 

Y Trichant - The 300m Hills of Wales by Myrddyn Phillips

The name the hill is listed by is Moel Caws, and it is adjoined to the Arenig group of hills, which are situated in the central part of North Wales (Region A, Sub-Region A3), and it is positioned with the A494 road to its east, and has the town of Y Bala 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, 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 367m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and an estimated c 344m bwlch height, based on interpolation of 10m contouring between 340m – 350m that appears on the Ordnance Survey 1:25,000 Explorer map. 

Extract from the Ordnance Survey 1:25,000 Explorer map

However, it was not until LIDAR became available that the details for this hill could be accurately re-assessed.  The LIDAR (Light Detection & Ranging) technique produced highly accurate height data that is now freely available for much of England and Wales. 

Therefore, the confirmation of the addition of this hill to Sub-Trichant status is due to LIDAR analysis, resulting in a 365.1m summit height and a 340.9m bwlch height, with these values giving this hill 24.2m of drop, which is sufficient for it to be classified as a Sub-Trichant. 

 

The full details for the hill are: 

Group:  Arenig 

Name:  Moel Caws 

OS 1:50,000 map:  124, 125

Summit Height:  365.1m (LIDAR)                                                           

Summit Grid Reference:  SH 84619 27866 (LIDAR) 

Bwlch Height:  340.9m (LIDAR) 

Bwlch Grid Reference:  SH 84438 27876 (LIDAR) 

Drop:  24.2m (LIDAR) 

 

Myrddyn Phillips (December 2021)




Mapping Mountains - Hill Reclassifications - Y Trichant

Allt y Gwine (SH 834 253) – Sub-Trichant addition (112th 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 LIDAR analysis conducted by Myrddyn Phillips. 

LIDAR image of Allt y Gwine (SH 834 253)

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. 

Y Trichant - The 300m Hills of Wales by Myrddyn Phillips

The name the hill is listed by is Allt y Gwine, and it is adjoined to the Arenig group of hills, which are situated in the central part of North Wales (Region A, Sub-Region A3), and it is positioned with the A494 road to its south-east, and has the town of Y Bala towards the 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, 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 376m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and an estimated c 354m bwlch height, based on interpolation of 10m contouring between 350m – 360m that appears on the Ordnance Survey 1:25,000 Explorer map. 

Extract from the Ordnance Survey 1:25,000 Explorer map

However, it was not until LIDAR became available that the details for this hill could be accurately re-assessed.  The LIDAR (Light Detection & Ranging) technique produced highly accurate height data that is now freely available for much of England and Wales. 

Therefore, the confirmation of the addition of this hill to Sub-Trichant status is due to LIDAR analysis, resulting in a 375.6m summit height and a 351.5m bwlch height, with these values giving this hill 24.1m of drop, which is sufficient for it to be classified as a Sub-Trichant. 

 

The full details for the hill are: 

Group:  Arenig 

Name:  Allt y Gwine 

OS 1:50,000 map:  124, 125

Summit Height:  375.6m (LIDAR)                                                           

Summit Grid Reference:  SH 83445 25393 (LIDAR) 

Bwlch Height:  351.5m (LIDAR) 

Bwlch Grid Reference:  SH 83776 25877 (LIDAR) 

Drop:  24.1m (LIDAR) 

 

Myrddyn Phillips (December 2021)




Mapping Mountains - Hill Reclassifications - Y Trichant

Ffridd Felen (SH 855 388) – Sub-Trichant addition (111th reclassification)

Significant Height Revisions post for Ffridd Felen

 

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 LIDAR analysis initially conducted by Aled Williams and subsequently by Myrddyn Phillips. 

LIDAR image of Ffridd Felen (SH 855 388)

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. 

Y Trichant - The 300m Hills of Wales by Myrddyn Phillips

The name the hill is listed by is Ffridd Felen, and it is adjoined to the Arenig group of hills, which are situated in the central part of North Wales (Region A, Sub-Region A3), and it is positioned with a minor road to its north-east and the A4212 road to its north-west, and has the town of Y Bala 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, 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 an estimated c 21m of drop, based on the 392m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and an estimated c 371m bwlch height, with the latter based on interpolation of 10m contouring between 370m – 380m that appear on the Ordnance Survey 1:25,000 Explorer map. 

Extract from the Ordnance Survey 1:25,000 Explorer map

However, it was not until LIDAR became available that the details for this hill could be accurately re-assessed.  The LIDAR (Light Detection & Ranging) technique produced highly accurate height data that is now freely available for much of England and Wales. 

Therefore, the confirmation of the addition of this hill to Sub-Trichant status is due to LIDAR analysis, resulting in a 395.0m summit height and a 372.0m bwlch height, with these values giving this hill 23.0m of drop, which is sufficient for it to be classified as a Sub-Trichant. 

 

The full details for the hill are: 

Group:  Arenig 

Name:  Ffridd Felen 

OS 1:50,000 map:  124, 125

Summit Height:  395.0m (LIDAR)                                                           

Summit Grid Reference:  SH 85563 38821 (LIDAR) 

Bwlch Height:  372.0m (LIDAR) 

Bwlch Grid Reference:  SH 85597 38395 (LIDAR) 

Drop:  23.0m (LIDAR) 

 

Myrddyn Phillips (December 2021)




Mapping Mountains - Hill Reclassifications - Y Trichant

Cefn Llwyd (SH 724 309) – Sub-Trichant addition (110th reclassification)

Significant Name Changes post for Cefn Llwyd


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 LIDAR analysis conducted by Myrddyn Phillips. 

LIDAR image of Cefn Llwyd (SH 724 309)

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. 

Y Trichant - The 300m Hills of Wales by Myrddyn Phillips

The name the hill is listed by is Cefn Llwyd and this was derived from the Tithe map, and it is adjoined to the Arenig group of hills, which are situated in the central part of North Wales (Region A, Sub-Region A3), and it is positioned with the A470 road to its west and minor roads to its north and east, and has the village of Trawsfynydd towards the north 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, 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 an estimated c 20m of drop, based on an estimated c 363m summit height and an estimated c 343m bwlch height, with both heights based on interpolation of 10m contouring that appear on the Ordnance Survey 1:25,000 Explorer map. 

Extract from the Ordnance Survey 1:25,000 Explorer map

However, it was not until LIDAR became available that the details for this hill could be accurately re-assessed.  The LIDAR (Light Detection & Ranging) technique produced highly accurate height data that is now freely available for much of England and Wales. 

Therefore, the confirmation of the addition of this hill to Sub-Trichant status is due to LIDAR analysis, resulting in a 363.0m summit height and a 339.8m bwlch height, with these values giving this hill 23.2m of drop, which is sufficient for it to be classified as a Sub-Trichant. 

 

The full details for the hill are: 

Group:  Arenig 

Name:  Cefn Llwyd 

OS 1:50,000 map:  124

Summit Height:  363.0m (LIDAR)                                                           

Summit Grid Reference:  SH 72478 30978 (LIDAR) 

Bwlch Height:  339.8m (LIDAR) 

Bwlch Grid Reference:  SH 72478 30541 (LIDAR) 

Drop:  23.2m (LIDAR) 

 

Myrddyn Phillips (December 2021)




Mapping Mountains - Hill Reclassifications - Y Trichant

Sheep Pasture (SN 935 821) – Sub-Trichant deletion (109th reclassification)

Significant Name Changes post for Sheep Pasture

 

There has been a deletion to the list of Y Trichant – The 300m Hills of Wales, with the summit height, bwlch height and their locations, the drop and status of the hill derived from LIDAR analysis and a subsequent Trimble GeoXH 6000 survey conducted by Myrddyn Phillips. 

Sheep Pasture (SN 935 821)

The criteria for the list that this deletion 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. 

Y Trichant - The 300m Hills of Wales by Myrddyn Phillips

The name the hill is listed by is Sheep Pasture and this was derived from the Tithe map and it is adjoined to the Pumlumon group of hills, which are situated in the north-western part of Mid and West Wales (Region B, Sub-Region B2), and it is positioned with a minor road to its north-west and the A470 road to its south-east, and has the town of Llanidloes 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 not included in the Hills to be surveyed sub 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 an estimated c 21m of drop, based on the 356m summit spot height that appears on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map and an estimated c 335m bwlch height based on interpolation of 10m contouring between 330m – 340m. 

Extract from the Ordnance Survey 1:25,000 Explorer map

However, it was not until LIDAR became available that the details for this hill could be accurately re-assessed.  The LIDAR (Light Detection & Ranging) technique produced highly accurate height data that is now freely available for much of England and Wales. 

LIDAR image of Sheep Pasture (SN 935 821)

The result produced by LIDAR analysis gives this hill less than 20m of drop, and as the summit has now been surveyed with the Trimble GeoXH 6000 it is this result that is being prioritised for listing purposes. 

The Trimble GeoXH 6000 gathering data at the summit of Sheep Pasture

Therefore, the deletion of this hill from Sub-Trichant status is due to LIDAR bwlch analysis and a Trimble GeoXH 6000 summit survey, resulting in a 355.3m summit height and a 336.4m bwlch height, with these values giving this hill 18.9m of drop, which is insufficient for it to be classified as a Sub-Trichant.

 

The full details for the hill are: 

Group:  Pumlumon 

Name:  Sheep Pasture 

OS 1:50,000 map:  136

Summit Height:  355.3m (converted to OSGM15, Trimble GeoXH 6000)

Summit Grid Reference:  SN 93587 82145 (Trimble GeoXH 6000) 

Bwlch Height:  336.4m (LIDAR) 

Bwlch Grid Reference:  SN 93150 82163 (LIDAR) 

Drop:  18.9m (Trimble GeoXH 6000 summit and LIDAR bwlch) 

 

Myrddyn Phillips (November 2021)

 



Mapping Mountains - Hill Reclassifications - Y Trichant

Bryn Bedd (SN 671 475) – Sub-Trichant reclassified to Trichant (108th reclassification)

 

There has been a reclassification to the list of Y Trichant – The 300m Hills of Wales, with the summit height, bwlch height and their locations, the drop and status of the hill derived from LIDAR analysis conducted by Myrddyn Phillips. 

LIDAR image of Bryn Bedd (SN 671 475)

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. 

Y Trichant - The 300m Hills of Wales by Myrddyn Phillips

The name the hill is listed by is Bryn Bedd and it is adjoined to the Elenydd group of hills, which are situated in the central part of the Mid and West Wales Region (Region B, Sub-Region B2), and it is positioned with minor roads to its north-west and south, and has the village of Ffarmers towards the south-west. 

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 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 28m of drop, based on the 354m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and an estimated c 326m bwlch height based on interpolation of 10m contouring between 320m – 330m. 

Extract from the Ordnance Survey 1:25,000 Explorer map

When The Welsh P15s list was being compiled the details for this hill were re-assessed and the bwlch height amended to an estimated c 325m, and when coupled with this hill’s 354m summit spot 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 353.9m summit height and a 322.3m bwlch height, with these values giving this hill 31.5m of drop, which is sufficient for it to be classified as a Trichant. 

 

The full details for the hill are: 

Group:  Elenydd 

Name:  Bryn Bedd 

OS 1:50,000 map:  146

Summit Height:  353.9m (LIDAR)                                                           

Summit Grid Reference:  SN 67137 47549 (LIDAR) 

Bwlch Height:  322.3m (LIDAR) 

Bwlch Grid Reference:  SN 67294 47369 (LIDAR) 

Drop:  31.5m (LIDAR) 

 

Myrddyn Phillips (November 2021)




Mapping Mountains - Hill Reclassifications - Y Trichant

Pen y Bryn (SH 978 407) – Sub-Trichant addition (107th reclassification)

Significant Name Changes post for Pen y Bryn


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 LIDAR analysis conducted by Myrddyn Phillips. 

Pen y Bryn (SH 978 407)

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. 

Y Trichant - The 300m Hills of Wales by Myrddyn Phillips

The name the hill is listed by is Pen y Bryn and this was derived from the Tithe map, and it is adjoined to the Arenig group of hills, which are situated in the central part of North Wales (Region A, Sub-Region A3), and it is positioned with a minor road to its north-west and the A494 road to its south-east, and has the town of Y Bala towards the south-west. 

When the original 300m height band of Welsh P30 hills were published on Geoff Crowder’s v-g.me website, this hill was not included in the Hills to be surveyed sub list, 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 an estimated c 20m of drop, based on the 352m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and an estimated c 332m bwlch height, based on interpolation of 10m contouring between 330m – 340m. 

Extract from the Ordnance Survey 1:25,000 Explorer map

However, it was not until LIDAR became available that the details for this hill could be accurately re-assessed.  The LIDAR (Light Detection & Ranging) technique produced highly accurate height data that is now freely available for much of England and Wales. 

LIDAR image of Pen y Bryn (SH 978 407)

Therefore, the confirmation of the addition of this hill to Sub-Trichant status is due to LIDAR analysis, resulting in a 353.1m summit height and a 330.3m bwlch height, with these values giving this hill 22.75m of drop, which is sufficient for it to be classified as a Sub-Trichant. 

 

The full details for the hill are: 

Group:  Arenig 

Name:  Pen y Bryn 

OS 1:50,000 map:  125

Summit Height:  353.1m (LIDAR)                                                           

Summit Grid Reference:  SH 97898 40730 (LIDAR) 

Bwlch Height:  330.3m (LIDAR) 

Bwlch Grid Reference:  SH 97766 40488 (LIDAR) 

Drop:  22.75m (LIDAR) 

 

Myrddyn Phillips (November 2021)

 



Mapping Mountains - Hill Reclassifications - Y Trichant

Garth (SH 980 392) – Trichant reclassified to Sub-Trichant (106th reclassification)


There has been a reclassification to the list of Y Trichant – The 300m Hills of Wales, with the summit height, bwlch height and their locations, the drop and status of the hill derived from LIDAR analysis conducted by Myrddyn Phillips. 

LIDAR image of Garth (SH 980 392)

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. 

Y Trichant - The 300m Hills of Wales by Myrddyn Phillips

The name the hill is listed by is Garth, and it is adjoined to the Arenig group of hills, which are situated in the central part of North Wales (Region A, Sub-Region A3), and it is positioned with the A494 road to its north-west, a minor road to its south-west and the B4402 road to its south-east, and has the town of Y Bala towards the south-west. 

When the original 300m height band of Welsh P30 hills were published on Geoff Crowder’s v-g.me website, this hill was included in the Hills to be surveyed sub list, 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 29m of drop, based on an estimated c 307m summit height and an estimated c 278m bwlch height, with both heights based on interpolation of 10m contouring that appears on the Ordnance Survey 1:25,000 Explorer map. 

Extract from the Ordnance Survey 1:25,000 Explorer map

Since publication of the P30 lists of 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 old Ordnance Survey Vector Map Local hosted on the Geograph website and which was entitled the Interactive Coverage Map. 

The details for this hill were re-assessed when the Ordnance Survey Vector Map Local hosted on the Geograph website and which was entitled the Interactive Coverage Map became available online.  This mapping had many spot heights not on other publicly available maps and for this hill it had a 309m summit spot height positioned at SH 98123 39317, and when coupled with the estimated c 278m bwlch height gave this hill an estimated c 31m of drop and therefore it was reclassified to a Trichant. 

However, it was not until LIDAR became available that the details for this hill could be accurately re-assessed.  The LIDAR (Light Detection & Ranging) technique produced highly accurate height data that is now freely available for much of England and Wales. 

Therefore, the reclassification of this hill to Sub-Trichant status is due to LIDAR analysis, resulting in a 308.6m summit height and a 280.15m bwlch height, with these values giving this hill 28.5m of drop, which is insufficient for it to be classified as a Trichant. 

 

The full details for the hill are: 

Group:  Arenig 

Name:  Garth 

OS 1:50,000 map:  125

Summit Height:  308.6m (LIDAR)                                                           

Summit Grid Reference:  SH 98081 39259 (LIDAR) 

Bwlch Height:  280.15m (LIDAR) 

Bwlch Grid Reference:  SH 97706 38862 (LIDAR) 

Drop:  28.5m (LIDAR) 

 

Myrddyn Phillips (October 2021)









 

No comments: