Tuesday 29 August 2023

Mapping Mountains – Summit Relocations – Y Trichant - The 300m Hills of Wales

 

Y Trichant – The 300m Hills of Wales  Summit Relocations

Y Trichant - The 300m Hills of Wales are all Welsh hills at and above 300m and below 40om in height that have 30m minimum drop.  These hills form 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 qualification to this sub category being all Welsh hills at and above 300m and below 400m in height with 20m or more and below 30m of drop, with the Introduction to this list giving its publication history appearing 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 summit relocations to the main P30 list and the sub list appear below presented chronologically in receding order.








Mapping Mountains - Summit Relocations - Y Trichant

Crugiau Dwy (SN 171 311) - 5th summit relocation

Significant Height Revisions post for Crugiau Dwy

 

There has been a Summit Relocation to a hill that is listed in the 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 Crugiau Dwy (SN 171 311)

The criteria for the list that this summit relocation applies to:

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 Crugiau Dwy, and it is adjoined to the Mynydd Preseli group of hills, which are situated in the south-western part of South Wales (Region B, Sub-Region B1), and it is positioned with minor roads to its north and south-east, and the A478 road to its east, and has the village of Crymych towards the north north-east.

When the original 300m height band of Welsh P30 hills were published on Geoff Crowder’s v-g.me website, this hill was included in the main P30 list with a 359m summit height, based on the spot height positioned at SN 17141 31170 that appears on the contemporary Ordnance Survey 1:50,000 Landranger and 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 analysis gives the highest ground on this hill as 360.45m positioned at SN 17148 31171 and SN 17150 31172.  However, this is a part of a raised field boundary and protocols dictate that as this is deemed a relatively recent man-made construct such ground is discounted from the height of a hill. 

LIDAR summit image of Crugiau Dwy (SN 171 311)

The height produced by LIDAR analysis to the natural summit of this hill is 360.3m positioned at SN 17129 31154 and SN 17133 31187, and this position in relation to the raised field boundary comes within the parameters of the Summit Relocations used within this page heading, these parameters are:

The term Summit Relocations applies when the high point of the hill is found to be positioned; in a different field, to a different feature such as in a conifer plantation,  within a different map contour, to a different point where a number of potential summit positions are within close proximity, when natural ground or the natural and intact summit of a hill is confirmed compared to a higher point such as a raised field boundary or covered reservoir that is considered a relatively recent man-made construct, or a relocation of approximately 100 metres or more in distance from either the position of a map spot height or from where the summit of the hill was previously thought to exist.

Therefore, the summit height produced by LIDAR analysis is 360.3m and this is positioned at SN 17129 31154 and SN 17133 31187, this position is relatively close to where the 359m spot height appears on the Ordnance Survey 1:25,000 Explorer map, and is approximately 15 metres north-westward from where the high point of the raised field boundary is positioned. 

 

The full details for the hill are:

Group:  Mynydd Preseli 

Name:  Crugiau Dwy 

OS 1:50,000 map:  145

Summit Height:  360.3m (LIDAR)                                                           

Summit Grid Reference (New Position):  SN 17129 31154 & SN 17133 31187 (LIDAR) 

Bwlch Height:  321.5m (LIDAR) 

Bwlch Grid Reference:  SN 16431 30609 & SN 16432 30606 (LIDAR) 

Drop:  38.8m (LIDAR) 

 

Myrddyn Phillips (October 2024)




Mapping Mountains - Summit Relocations - Y Trichant

Lan Ucha Ty’n y Wern (SN 996 423) - 54th summit relocation

Significant Name Changes post for Lan Ucha Ty'n y Wern

 

There has been a Summit Relocation to a hill that is listed in the Y Trichant – The 300m Hills of Wales and the Y Pedwarau – The 400m 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 Lan Ucha Ty'n y Wern (SN 996 423)

The criteria for the lists this summit relocation affects 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

Y Pedwarau – The 400m Hills of Wales – Welsh hills at or above 400m and below 500m in height that have 30m minimum drop, accompanying the main list are five categories of sub hills, with this hill listed in the 390m Sub-Pedwar category.  The criteria for this category are all Welsh hills at or above 390m and below 400m in height that have 30m minimum drop.  The list is co-authored by Myrddyn Phillips and Aled Williams and is published on Mapping Mountains in Google Doc format.

Y Pedwarau - The 400m Hills of Wales by Myrddyn Phillips and Aled Williams

The name the hill is now listed by is Lan Ucha Ty’n y Wern 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 B4519 road to its north-east and a minor road to its south, and has the small community of Capel Uchaf (Upper Chapel) towards the south-east.

When the original 300m height band of Welsh P30 hills were published on Geoff Crowder’s v-g.me website, this hill was included in the main P30 list with a 398m summit height, based on the spot height positioned at SN 996 423 that appears on the contemporary 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 analysis gives the highest ground on this hill as 396.9m positioned at SN 99625 42340.  However, this is a part of a raised field boundary and protocols dictate that as this is deemed a relatively recent man-made construct such ground is discounted from the height of a hill. 

LIDAR summit image of Lan Ucha Ty'n y Wern (SN 996 423)

The height produced by LIDAR analysis to the natural summit of this hill is 396.7m positioned at SN 99632 42324, and this position in relation to raised field boundary comes within the parameters of the Summit Relocations used within this page heading, these parameters are:

The term Summit Relocations applies when the high point of the hill is found to be positioned; in a different field, to a different feature such as in a conifer plantation,  within a different map contour, to a different point where a number of potential summit positions are within close proximity, when natural ground or the natural and intact summit of a hill is confirmed compared to a higher point such as a raised field boundary or covered reservoir that is considered a relatively recent man-made construct, or a relocation of approximately 100 metres or more in distance from either the position of a map spot height or from where the summit of the hill was previously thought to exist.

Therefore, the summit height produced by LIDAR analysis is 396.7m and this is positioned at SN 99632 42324, this position is close to where the 398m spot height appears on the Ordnance Survey 1:25,000 Explorer map, and is approximately 16 metres south-eastward from where the high point of the raised field boundary is positioned. 

 

The full details for the hill are:

Group:  Mynydd Epynt 

Name:  Lan Ucha Ty’n y Wern 

OS 1:50,000 map:  147, 160

Summit Height:  396.7m (LIDAR)                                                           

Summit Grid Reference (New Position):  SN 99632 42324 (LIDAR) 

Bwlch Height:  362.65m (LIDAR) 

Bwlch Grid Reference:  SN 99601 42833 (LIDAR) 

Drop:  34.1m (LIDAR) 

 

Myrddyn Phillips (July 2024) 




Mapping Mountains - Summit Relocations - Y Trichant

Pt. 364.9m (SN 901 346) - 53rd summit relocation

Significant Name Changes post for Pt. 364.9m

 

There has been a Summit Relocation to a hill that is listed in the 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. 364.9m (SN 901 346)

The criteria for the list that this summit relocation 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. 364.9m) notation as an appropriate name for it either through local enquiry and/or historic research has not been found by the author, and it is adjoined to the Mynydd Epynt group of hills, which are situated in the central part of South Wales (Region B, Sub-Region B1), and it is positioned encircled by minor roads, with the A40 road farther to its south, and has the village of Pontsenni (Sennybridge) towards the south south-east.

When the original 300m height band of Welsh P30 hills were published on Geoff Crowder’s v-g.me website, this hill was included in the Hills to be surveyed sub list with a summit height of 364m, based on the spot height positioned at SN 90147 34587 that appears on the contemporary Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map. 

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 25m of drop, based on the 364m summit spot height and the 339m 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.

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 analysis gives the highest ground on this hill as 366.1m positioned at SN 90164 34612.  However, this is a part of a raised track/field boundary and protocols dictate that as this is deemed a relatively recent man-made construct such ground is discounted from the height of a hill. 

LIDAR summit image of Pt. 364.9m (SN 901 346)

The height produced by LIDAR analysis to the natural summit of this hill is 364.9m positioned at SN 90152 34612, and this position in relation to raised track/field boundary comes within the parameters of the Summit Relocations used within this page heading, these parameters are:

The term Summit Relocations applies when the high point of the hill is found to be positioned; in a different field, to a different feature such as in a conifer plantation,  within a different map contour, to a different point where a number of potential summit positions are within close proximity, when natural ground or the natural and intact summit of a hill is confirmed compared to a higher point such as a raised field boundary or covered reservoir that is considered a relatively recent man-made construct, or a relocation of approximately 100 metres or more in distance from either the position of a map spot height or from where the summit of the hill was previously thought to exist.

Therefore, the summit height produced by LIDAR analysis is 364.9m and this is positioned at SN 90152 34612, this is relatively close to where the spot height is positioned and is approximately 12 metres westward from the high point of the raised track/field boundary. 

 

The full details for the hill are:

Group:  Mynydd Epynt 

Name:  Pt. 364.9m 

OS 1:50,000 map:  160

Summit Height:  364.9m (LIDAR)                                                           

Summit Grid Reference (New Position):  SN 90152 34612 (LIDAR)                                        

Bwlch Height:  339.0m (LIDAR) 

Bwlch Grid Reference:  SN 90131 34941 (LIDAR) 

Drop:  25.9m (LIDAR) 

 

Myrddyn Phillips (June 2024)




Mapping Mountains - Summit Relocations - Y Trichant

Crug y Gorllwyn (SN 321 340) - 52nd summit relocation

 

There has been a Summit Relocation to a hill that is listed in the 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 Crug y Gorllwyn (SN 321 340)

The criteria for the list that this summit relocation 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 Crug y Gorllwyn, and it is adjoined to the Mynydd Pencarreg group of hills, which are situated in the south-western part of South Wales (Region B, Sub-Region B1), and it is positioned with minor roads to its north, west and south, and the B4333 road to its east, and has the town of Castell Newydd Emlyn (Newcastle Emlyn) towards the north.

When the original 300m height band of Welsh P30 hills were published on Geoff Crowder’s v-g.me website, this hill was included in the Hills to be surveyed sub list with a summit height of 326m, based on the spot height adjoined to a triangulation pillar positioned at SN 32185 34085 that appears on the contemporary Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map. 

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 28m of drop, based on the 326m summit spot height and the 298m 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.

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 analysis gives the highest ground on this hill as 327.5m positioned at SN 32249 34121 and SN 32258 34125.  However, this is a part of a covered reservoir and protocols dictate that as this is deemed a relatively recent man-made construct such ground is discounted from the height of a hill. 

LIDAR summit image of Crug y Gorllwyn (SN 321 340)

The height produced by LIDAR analysis to the summit of this hill is 326.2m positioned at SN 32186 34079, and this position in relation to covered reservoir comes within the parameters of the Summit Relocations used within this page heading, these parameters are:

The term Summit Relocations applies when the high point of the hill is found to be positioned; in a different field, to a different feature such as in a conifer plantation,  within a different map contour, to a different point where a number of potential summit positions are within close proximity, when natural ground or the natural and intact summit of a hill is confirmed compared to a higher point such as a raised field boundary or covered reservoir that is considered a relatively recent man-made construct, or a relocation of approximately 100 metres or more in distance from either the position of a map spot height or from where the summit of the hill was previously thought to exist.

Therefore, the summit height produced by LIDAR analysis is 326.2m and this is positioned at SN 32186 34079, this position is beside the triangulation pillar and is approximately 63 metres south-westward from the high point of the covered reservoir. 

 

The full details for the hill are:

Group:  Mynydd Pencarreg 

Name:  Crug y Gorllwyn 

OS 1:50,000 map:  145

Summit Height:  326.2m (LIDAR)                                                           

Summit Grid Reference (New Position):  SN 32186 34079 (LIDAR)                                        

Bwlch Height:  297.1m (LIDAR) 

Bwlch Grid Reference:  SN 32843 35432 (LIDAR) 

Drop:  29.1m (LIDAR) 

 

Myrddyn Phillips (May 2024) 




Mapping Mountains - Summit Relocations - Y Trichant

Moelfre (SN 326 361) - 51st summit relocation

 

There has been a Summit Relocation to a hill that is listed in the 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 Moelfre (SN 326 361)

The criteria for the list that this summit relocation 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 Moelfre, and it is adjoined to the Mynydd Pencarreg group of hills, which are situated in the south-western part of South Wales (Region B, Sub-Region B1), and it is positioned with minor roads to its north-west, west and south, and the B4333 road to its east, and has the town of Castell Newydd Emlyn (Newcastle Emlyn) 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 included in the main P30 list with a summit height of 335m, based on the spot height that appears on the contemporary Ordnance Survey 1:50,000 Landranger and 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 104m of drop, based on the 335m summit spot height positioned at SN 32648 36095 and the 231m 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 1:25,000 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 analysis gives the highest ground on this hill as 335.4m positioned at SN 32685 36114.  However, although this is positioned atop an ancient tumulus which under the protocols used for this list qualifies for the height of a hill, LIDAR contouring implies the height has been artificially raised by a field boundary positioned on the tumulus and protocols dictate that as this is deemed a relatively recent man-made construct such ground is discounted from the height of a hill. 

LIDAR summit image of Moelfre (SN 326 361)

The height produced by LIDAR analysis to the qualifying summit of this hill is 335.3m positioned at SN 32616 36119 and SN 32619 36117, and this position in relation to the raised field boundary comes within the parameters of the Summit Relocations used within this page heading, these parameters are:

The term Summit Relocations applies when the high point of the hill is found to be positioned; in a different field, to a different feature such as in a conifer plantation,  within a different map contour, to a different point where a number of potential summit positions are within close proximity, when natural ground or the natural and intact summit of a hill is confirmed compared to a higher point such as a raised field boundary or covered reservoir that is considered a relatively recent man-made construct, or a relocation of approximately 100 metres or more in distance from either the position of a map spot height or from where the summit of the hill was previously thought to exist.

Therefore, the summit height produced by LIDAR analysis is 335.3m and this is positioned at SN 32616 36119 and SN 32619 36117, this position is not given a spot height on the contemporary Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map and is approximately 33 metres north-westward from where the 335m spot height appears and approximately 70 metres westward from the high point of the raised field boundary. 

 

The full details for the hill are:

Group:  Mynydd Pencarreg 

Name:  Moelfre 

OS 1:50,000 map:  145

Summit Height:  335.3m (LIDAR)                                                           

Summit Grid Reference (New Position):  SN 32616 36119 & SN 32619 36117 (LIDAR)

Bwlch Height:  231.0m (LIDAR) 

Bwlch Grid Reference:  SN 41888 33712 (LIDAR) 

Drop:  104.4m (LIDAR)

 

Myrddyn Phillips (May 2024)

 



Mapping Mountains - Summit Relocations - Y Trichant

Llanfilo Camp (SO 113 327) - 50th summit relocation

Significant Height Revisions post for Llanfilo Camp

Significant Name Changes post for Llanfilo Camp

 

There has been a Summit Relocation to a hill that is listed in the 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 Llanfilo Camp (SO 113 327)

The criteria for the list that this summit relocation 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 Llanfilo Camp and this was derived from information supplied by Coflein, 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 encircled by minor roads, with the A38 road farther to its north and the B4560 road farther to its east, and has the town of Talgarth 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 included in the main P30 list with a 310m summit height adjoined to a triangulation pillar positioned at SO 11359 32761 that appears on the contemporary Ordnance Survey 1:50,000 Landranger and 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 summit image of Llanfilo Camp (SO 113 327)

LIDAR analysis gives the highest ground on this hill as 310.4m positioned at SO 11352 32709, and this in relation to the previously listed summit position which LIDAR analysis gives as 310.0m in height and positioned at SO 11351 32749 comes within the parameters of the Summit Relocations used within this page heading, these parameters are:

The term Summit Relocations applies when the high point of the hill is found to be positioned; in a different field, to a different feature such as in a conifer plantation,  within a different map contour, to a different point where a number of potential summit positions are within close proximity, when natural ground or the natural and intact summit of a hill is confirmed compared to a higher point such as a raised field boundary or covered reservoir that is considered a relatively recent man-made construct, or a relocation of approximately 100 metres or more in distance from either the position of a map spot height or from where the summit of the hill was previously thought to exist.

Therefore, the summit height produced by LIDAR analysis is 310.4m and this is positioned at SO 11352 32709, this position is not given a spot height or a 310m contour ring on the contemporary Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map, and is approximately 40 metres southward from where the previously listed summit is positioned and importantly to a different feature; being relocated from a triangulation pillar to an ancient earthwork. 

 

The full details for the hill are:

Group:  Mynydd Epynt 

Name:  Llanfilo Camp 

OS 1:50,000 map:  161

Summit Height:  310.4m (LIDAR)                                                           

Summit Grid Reference (New Position):  SO 11352 32709 (LIDAR) 

Bwlch Height:  223.6m (LIDAR) 

Bwlch Grid Reference:  SO 09879 31998 (LIDAR) 

Drop:  86.8m (LIDAR) 

 

Myrddyn Phillips (April 2024)




Mapping Mountains - Summit Relocations - Y Trichant

Mynydd y Garth (SN 711 081) - 49th summit relocation

 

There has been a Summit Relocation to a hill that is listed in the 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 y Garth (SN 711 081)

The criteria for the list that this summit relocation 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 y Garth and it is adjoined to the Mynydd Du group of hills, which are situated in the southern part of South Wales (Region B, Sub-Region B5), and it is positioned with a minor road to its north and east, and the A474 road to its west, and has the town of Pontardawe towards the south. 

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

When the original 300m height band of Welsh P30 hills were published on Geoff Crowder’s v-g.me website, this hill was included in the accompanying sub list with a 321m summit height, based on the spot height that appears on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map and which is positioned at SN 71293 08388. 

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 summit image of Mynydd y Garth (SN 711 081)

LIDAR analysis gives the highest ground on this hill as 321.8m positioned at SN 71149 08116, and this in relation to the previously listed summit position which LIDAR analysis gives as 321.0m in height and positioned at SN 71306 08392 comes within the parameters of the Summit Relocations used within this page heading, these parameters are:

The term Summit Relocations applies when the high point of the hill is found to be positioned; in a different field, to a different feature such as in a conifer plantation,  within a different map contour, to a different point where a number of potential summit positions are within close proximity, when natural ground or the natural and intact summit of a hill is confirmed compared to a higher point such as a raised field boundary or covered reservoir that is considered a relatively recent man-made construct, or a relocation of approximately 100 metres or more in distance from either the position of a map spot height or from where the summit of the hill was previously thought to exist.

Therefore, the summit height produced by LIDAR analysis is 321.8m and this is positioned at SN 71149 08116, this position is not given a spot height on the contemporary Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map, and is approximately 280 metres south south-westward from where the previously listed summit is positioned. 

 

The full details for the hill are:

Group:  Mynydd Du 

Name:  Mynydd y Garth 

OS 1:50,000 map:  160

Summit Height:  321.8m (LIDAR)                                                           

Summit Grid Reference (New Position):  SN 71149 08116 (LIDAR) 

Bwlch Height:  296.1m (LIDAR) 

Bwlch Grid Reference:  SN 71524 08760 (LIDAR) 

Drop:  25.7m (LIDAR) 

 

Myrddyn Phillips (March 2024)

 



Mapping Mountains - Summit Relocations - Y Trichant

Cwm Helyg (SO 121 460) - 48th summit relocation

Significant Name Changes post for Cwm Helyg

 

There has been a Summit Relocation to a hill that is listed in the 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 produced by Joe Nuttall in his surface analysis programme, with subsequent LIDAR analysis conducted by the DoBIH team and independently by Myrddyn Phillips. 

LIDAR image of Cwm Helyg (SO 121 460)

The criteria for the list that this summit relocation 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 Cwm Helyg and this was derived from the Tithe map, and it is adjoined to the Gwaun Ceste group of hills, which are situated in the eastern part of South Wales (Region B, Sub-Region B3), and it is positioned with a minor road to its north and south-west, the A470 road farther to its west and the B4594 road to its south-east, and has the small community of Erwyd (Erwood) 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 with a summit height of 332m, based on the spot height that appears on the contemporary Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map.

After the sub list was standardised, and interpolated heights and drop values also included the details for this hill were re-evaluated and it was listed with an estimated c 26m of drop, based on the 332m summit spot height positioned at SO 12205 46007 and an estimated c 306m bwlch height, based on interpolation of 10m contouring between 300m – 310m. 

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 analysis gives the highest ground on this hill as 333.8m positioned at SO 12132 46026.  However, this is a part of an old raised field boundary and protocols dictate that as this is deemed a relatively recent man-made construct such ground is discounted from the height of a hill. 

LIDAR summit image of Cwm Helyg (SO 121 460)

The height produced by LIDAR analysis to the natural summit of this hill is 333.5m positioned at SO 12120 46030, and this position in relation to the old raised field boundary comes within the parameters of the Summit Relocations used within this page heading, these parameters are:

The term Summit Relocations applies when the high point of the hill is found to be positioned; in a different field, to a different feature such as in a conifer plantation,  within a different map contour, to a different point where a number of potential summit positions are within close proximity, when natural ground or the natural and intact summit of a hill is confirmed compared to a higher point such as a raised field boundary or covered reservoir that is considered a relatively recent man-made construct, or a relocation of approximately 100 metres or more in distance from either the position of a map spot height or from where the summit of the hill was previously thought to exist.

Therefore, the summit height produced by LIDAR analysis is 333.5m and this is positioned at SO 12120 46030, this position is not given a spot height on the contemporary Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map and is approximately 85 metres west north-westward from where the 332m spot height appears and approximately 12 metres west north-westward from the high point of the raised field boundary. 

 

The full details for the hill are:

Group:  Gwaun Ceste 

Name:  Cwm Helyg 

OS 1:50,000 map:  148

Summit Height:  333.5m (LIDAR)                                                           

Summit Grid Reference:  SO 12120 46030 (LIDAR) 

Bwlch Height:  303.8m (LIDAR) 

Bwlch Grid Reference:  SO 12449 46144 (LIDAR) 

Drop:  29.7m (LIDAR) 

 

Myrddyn Phillips (February 2024)




Mapping Mountains - Summit Relocations - Y Trichant

Lan Brynffo (SN 851 408) - 47th summit relocation

Hill Reclassifications post for Lan Brynffo

Significant Name Changes post for Lan Brynffo

 

There has been a Summit Relocation to a hill that is listed in the 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 Lan Brynffo (SN 851 408)

The criteria for the list that this summit relocation 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 Lan Brynffo 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 and west, and the A483 road farther to its north-west, and has the town of Llanwrtyd towards the north 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 25m of drop, based on the 338m summit spot height positioned at SN 85207 40874 that appears on the contemporary 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

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 analysis gives the highest ground on this hill as 338.04m positioned at SN 85201 40876.  However, this is a part of a raised field boundary and protocols dictate that as this is deemed a relatively recent man-made construct such ground is discounted from the height of a hill. 

LIDAR summit image of Lan Brynffo (SN 851 408)

The height produced by LIDAR analysis to the natural summit of this hill is 338.02m positioned at SN 85196 40863, and this position in relation to the raised field boundary comes within the parameters of the Summit Relocations used within this page heading, these parameters are:

The term Summit Relocations applies when the high point of the hill is found to be positioned; in a different field, to a different feature such as in a conifer plantation,  within a different map contour, to a different point where a number of potential summit positions are within close proximity, when natural ground or the natural and intact summit of a hill is confirmed compared to a higher point such as a raised field boundary or covered reservoir that is considered a relatively recent man-made construct, or a relocation of approximately 100 metres or more in distance from either the position of a map spot height or from where the summit of the hill was previously thought to exist.

Therefore, the summit height produced by LIDAR analysis is 338.0m and this is positioned at SN 85196 40863, this position is not given a spot height on the contemporary Ordnance Survey 1:25,000 Explorer map and is approximately 11 metres south-westward from where the 338m spot height appears on the Ordnance Survey 1:25,000 Explorer map and approximately 13 metres south-westward from the high point of the raised field boundary. 

 

The full details for the hill are:

Group:  Mynydd Epynt 

Name:  Lan Brynffo 

OS 1:50,000 map:  147, 160

Summit Height:  338.0m (LIDAR)                                                           

Summit Grid Reference:  SN 85196 40863 (LIDAR) 

Bwlch Height:  311.9m (LIDAR) 

Bwlch Grid Reference:  SN 85003 40781 & SN 85003 40772 (LIDAR) 

Drop:  26.1m (LIDAR) 

 

Myrddyn Phillips (February 2024)




Mapping Mountains - Summit Relocations - Y Trichant

Wstrws (SN 389 502) - 46th summit relocation

Hill Reclassifications post for Wstrws

Significant Name Changes post for Wstrws

 

There has been a Summit Relocation to a hill that is listed in the 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 Wstrws (SN 389 502)

The criteria for the list that this summit relocation 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 Wstrws and this was derived from the Tithe map, and it is adjoined to the Mynydd Bach group of hills, which are situated in the western part of South Wales (Region B, Sub-Region B1), and it is positioned with the A486 road to its north-west and minor roads to its south and east, and has the village of Post-mawr (Synod Inn) towards the north 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 22m of drop, based on the 308m summit spot height positioned at SN 38989 50309 that appears on the contemporary Ordnance Survey 1:25,000 Explorer map, and an estimated c 286m bwlch height, based on interpolation of 5m contouring between 285m – 290m. 

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 analysis gives the highest ground on this hill as 309.1m positioned at SN 38967 50318.  However, this is a part of a raised field boundary and protocols dictate that as this is deemed a relatively recent man-made construct such ground is discounted from the height of a hill. 

LIDAR summit image of Wstrws (SN 389 502)

The height produced by LIDAR analysis to the natural summit of this hill is 308.2m positioned at SN 38955 50296, and this position in relation to the raised field boundary comes within the parameters of the Summit Relocations used within this page heading, these parameters are:

The term Summit Relocations applies when the high point of the hill is found to be positioned; in a different field, to a different feature such as in a conifer plantation,  within a different map contour, to a different point where a number of potential summit positions are within close proximity, when natural ground or the natural and intact summit of a hill is confirmed compared to a higher point such as a raised field boundary or covered reservoir that is considered a relatively recent man-made construct, or a relocation of approximately 100 metres or more in distance from either the position of a map spot height or from where the summit of the hill was previously thought to exist.

Therefore, the summit height produced by LIDAR analysis is 308.2m and this is positioned at SN 38955 50296, this position is not given a spot height on the contemporary Ordnance Survey 1:25,000 Explorer map and is approximately 35 metres westward from where the 308m spot height appears on the Ordnance Survey 1:25,000 Explorer map and approximately 22 metres south-westward from the high point of the raised field boundary. 

 

The full details for the hill are:

Group:  Mynydd Bach 

Name:  Wstrws 

OS 1:50,000 map:  145

Summit Height:  308.2m (LIDAR)                                                           

Summit Grid Reference (New Position):  SN 38955 50296 (LIDAR) 

Bwlch Height:  286.3m (LIDAR) 

Bwlch Grid Reference:  SN 38557 50449 (LIDAR) 

Drop:  21.9m (LIDAR) 

 

Myrddyn Phillips (January 2024)




Mapping Mountains - Summit Relocations - Y Trichant

Pen Moel Hedog (SN 451 469) - 45th summit relocation

Hill Reclassifications post for Pen Moel Hedog

 

There has been a Summit Relocation to a hill that is listed in the 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 Pen Moel Hedog (SN 451 469)

The criteria for the list that this summit relocation 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 Pen Moel Hedog, and it is adjoined to the Mynydd Bach group of hills, which are situated in the western part of South Wales (Region B, Sub-Region B1), and it is positioned with the B4459 road to its west, the A475 road to its south and a minor road to its east, and has the town of Llanybydder 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 23m of drop, based on the 314m summit spot height positioned at SN 45142 46935 that appears on the contemporary Ordnance Survey 1:25,000 Explorer map, and an estimated c 291m bwlch height, based on interpolation of 5m contouring between 290m – 295m. 

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 analysis gives the highest ground on this hill as 313.5m positioned at SN 45168 46943.  However, this is a part of a raised field boundary and protocols dictate that as this is deemed a relatively recent man-made construct such ground is discounted from the height of a hill. 

LIDAR summit image of Pen Moel Hedog (SN 451 469)

The height produced by LIDAR analysis to the natural summit of this hill is 312.8m positioned at SN 45159 46968, and this position in relation to the raised field boundary comes within the parameters of the Summit Relocations used within this page heading, these parameters are:

The term Summit Relocations applies when the high point of the hill is found to be positioned; in a different field, to a different feature such as in a conifer plantation,  within a different map contour, to a different point where a number of potential summit positions are within close proximity, when natural ground or the natural and intact summit of a hill is confirmed compared to a higher point such as a raised field boundary or covered reservoir that is considered a relatively recent man-made construct, or a relocation of approximately 100 metres or more in distance from either the position of a map spot height or from where the summit of the hill was previously thought to exist.

Therefore, the summit height produced by LIDAR analysis is 312.8m and this is positioned at SN 45159 46968, this position is not given a spot height on the contemporary Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map and is approximately 35 metres north-eastward from where the 314m spot height appears on the Ordnance Survey 1:25,000 Explorer map and approximately 25 metres north north-westward from the high point of the raised field boundary. 

 

The full details for the hill are:

Group:  Mynydd Bach 

Name:  Pen Moel Hedog 

OS 1:50,000 map:  146

Summit Height:  312.8m (LIDAR)                                                           

Summit Grid Reference (New Position):  SN 45159 46968 (LIDAR) 

Bwlch Height:  289.8m (LIDAR) 

Bwlch Grid Reference:  SN 45622 48279 (LIDAR) 

Drop:  23.0m (LIDAR) 

 

Myrddyn Phillips (January 2024)




Mapping Mountains - Summit Relocations - Y Trichant

Rhos Ymryson (SN 460 499) - 44th summit relocation

Significant Height Revisions post for Rhos Ymryson

 

There has been a Summit Relocation to a hill that is listed in the Y Trichant – The 300m Hills of Wales and Y Trechol – The Dominant 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 Rhos Ymryson (SN 460 499)

The criteria for the two listings that this summit relocation 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

Y Trechol – The Dominant Hills of Wales – Welsh P30 hills whose prominence equal or exceed half that of their absolute height.  With the criteria for Lesser Dominant status being those additional Welsh P30 hills whose prominence is between one third and half that of their absolute height.  The list is authored by Myrddyn Phillips with the Introduction to the start of the Mapping Mountains publication of this list appearing on the 3rd December 2015, and the list is now available in its entirety on Mapping Mountains in Google Doc format. 

Y Trechol - The Dominant Hills of Wales by Myrddyn Phillips

The name the hill is listed by is Rhos Ymryson, and it is adjoined to the Mynydd Bach group of hills, which are situated in the western part of South Wales (Region B, Sub-Region B1), and it is positioned with the B4338 road to its north-east, a minor road to its north-west and the A475 road to its south, and has the village of Llanwenog towards the south-east. 

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

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

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 list with a 327m summit height, based on the spot height that appears on the contemporary Ordnance Survey 1:25,000 Explorer map and which is positioned at SN 459 500.  However, this height is given to the top of a covered reservoir, whilst the contemporary Ordnance Survey 1:50,000 Landranger map gives a 324m summit spot height, which conforms with the rounded up 1062ft (323.7m) height shown on the Ordnance Surveys series of Six-Inch maps. 

Extract from the Ordnance Survey series of Six-Inch maps

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

LIDAR analysis gives the highest ground on this hill as 326.6m positioned at SN 45999 50009.  However, this is to the top of a covered reservoir and protocols dictate that as this is deemed a relatively recent man-made construct such ground is discounted from the height of a hill. 

LIDAR summit image of Rhos Ymryson (SN 460 499)

The height produced by LIDAR analysis to the highest remaining natural ground on this hill is 323.3m and is positioned at SN 46032 49996, and this position in relation to the covered reservoir comes within the parameters of the Summit Relocations used within this page heading, these parameters are:

The term Summit Relocations applies when the high point of the hill is found to be positioned; in a different field, to a different feature such as in a conifer plantation,  within a different map contour, to a different point where a number of potential summit positions are within close proximity, when natural ground or the natural and intact summit of a hill is confirmed compared to a higher point such as a raised field boundary or covered reservoir that is considered a relatively recent man-made construct, or a relocation of approximately 100 metres or more in distance from either the position of a map spot height or from where the summit of the hill was previously thought to exist.

Therefore, the summit height produced by LIDAR analysis is 323.3m and this is positioned at SN 46032 49996, this position is not given a spot height on the contemporary Ordnance Survey 1:25,000 Explorer map, but is given a 324m spot height on the contemporary 1:50,000 Landranger map, and is approximately 33 metres east south-eastward from the high point of the covered reservoir. 

 

The full details for the hill are:

Group:  Mynydd Bach 

Name:  Rhos Ymryson 

OS 1:50,000 map:  146

Summit Height:  323.3m (LIDAR)                                                           

Summit Grid Reference (New Position):  SN 46032 49996 (LIDAR)                                    

Bwlch Height:  162.6m (LIDAR) 

Bwlch Grid Reference:  SN 61745 57992 (LIDAR) 

Drop:  160.8m (LIDAR) 

Dominance:  49.72% (LIDAR) 

 

Myrddyn Phillips (January 2024)




Mapping Mountains - Summit Relocations - Y Trichant

Rhos Garn Whilgarn (SN 451 517) - 43rd summit relocation

 

There has been a Summit Relocation to a hill that is listed in the 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 Rhos Garn Whilgarn (SN 451 517)

The criteria for the list that this summit relocation 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 Rhos Garn Whilgarn, and it is adjoined to the Mynydd Bach group of hills, which are situated in the western part of South Wales (Region B, Sub-Region B1), and it is positioned with a minor road to its west and east, and the B4338 road to its south-west, and has the village of Post-mawr (Synod Inn) 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 list with a summit height of 312m that appears as a spot height adjoined to a triangulation pillar positioned at SN 45117 51763 that appears on the contemporary Ordnance Survey 1:50,000 Landranger and 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 analysis gives the highest ground on this hill as 313.1m positioned at SN 45149 51777.  However, this is a part of a raised field boundary and protocols dictate that as this is deemed a relatively recent man-made construct such ground is discounted from the height of a hill. 

LIDAR summit image of Rhos Garn Whilgarn (SN 451 517)

The height produced by LIDAR analysis to the natural summit of this hill is 312.1m positioned at SN 45127 51754, and this position in relation to the raised field boundary comes within the parameters of the Summit Relocations used within this page heading, these parameters are:

The term Summit Relocations applies when the high point of the hill is found to be positioned; in a different field, to a different feature such as in a conifer plantation,  within a different map contour, to a different point where a number of potential summit positions are within close proximity, when natural ground or the natural and intact summit of a hill is confirmed compared to a higher point such as a raised field boundary or covered reservoir that is considered a relatively recent man-made construct, or a relocation of approximately 100 metres or more in distance from either the position of a map spot height or from where the summit of the hill was previously thought to exist.

Therefore, the summit height produced by LIDAR analysis is 312.1m and this is positioned at SN 45127 51754, this position is not given a spot height on the contemporary Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map and is approximately 23 metres south-westward from where the high point of the raised field boundary is positioned and approximately 10 metres south-eastward from where the triangulation pillar is positioned, which is also situated on the same raised field boundary. 

 

The full details for the hill are:

Group:  Mynydd Bach 

Name:  Rhos Garn Whilgarn 

OS 1:50,000 map:  146

Summit Height:  312.1m (LIDAR)                                                           

Summit Grid Reference (New Position):  SN 45127 51754 (LIDAR) 

Bwlch Height:  273.3m (LIDAR) 

Bwlch Grid Reference:  SN 45739 50729 (LIDAR) 

Drop:  38.8m (LIDAR) 

 

Myrddyn Phillips (January 2024) 




Mapping Mountains - Summit Relocations - Y Trichant

Trichrug (SN 541 599) - 42nd summit relocation

 

There has been a Summit Relocation to a hill that is listed in the 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 Trichrug (SN 541 599)

The criteria for the list that this summit relocation 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 Trichrug and it is adjoined to the Mynydd Bach group of hills, which are situated in the western part of South Wales (Region B, Sub-Region B1), and it is positioned with minor roads to its north-west and south-west, and the B4337 road to its immediate east, and has the town of Aberaeron 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 main P30 list with a 343m summit height, based on the spot height adjoined to a triangulation pillar that appears on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map and which is positioned at SN 54228 59915. 

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 summit image of Trichrug (SN 541 599)

LIDAR analysis gives the highest ground on this hill as 344.35m positioned at SN 54196 59952, and this in relation to the previously listed summit position comes within the parameters of the Summit Relocations used within this page heading, these parameters are:

The term Summit Relocations applies when the high point of the hill is found to be positioned; in a different field, to a different feature such as in a conifer plantation,  within a different map contour, to a different point where a number of potential summit positions are within close proximity, when natural ground or the natural and intact summit of a hill is confirmed compared to a higher point such as a raised field boundary or covered reservoir that is considered a relatively recent man-made construct, or a relocation of approximately 100 metres or more in distance from either the position of a map spot height or from where the summit of the hill was previously thought to exist.

Therefore, the summit height produced by LIDAR analysis is 344.35m and this is positioned at SN 54196 59952, this position is not given a spot height on the contemporary Ordnance Survey 1:50,000 Landranger and the 1:25,000 Explorer map, and is approximately 38 metres north-westward from where the previously listed summit is positioned and importantly positioned on a different tumulus which qualifies under the different feature protocol. 

 

The full details for the hill are:

Group:  Mynydd Bach 

Name:  Trichrug 

OS 1:50,000 map:  146

Summit Height:  344.35m (LIDAR)                                                           

Summit Grid Reference (New Position):  SN 54196 59952 (LIDAR) 

Bwlch Height:  270.1m (LIDAR) 

Bwlch Grid Reference:  SN 57812 61942 (LIDAR) 

Drop:  74.3m (LIDAR) 

 

Myrddyn Phillips (December 2023)




Mapping Mountains - Summit Relocations - Y Trichant

Cymanfynydd Fach (SN 562 615) - 41st summit relocation

Significant Name Changes post for Cymanfynydd Fach

 

There has been a Summit Relocation to a hill that is listed in the 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 Cymanfynydd Fach (SN 562 615)

The criteria for the list that this summit relocation 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 Cymanfynydd Fach and this was derived from the Tithe map, with research conducted by Iwan Wmffre for the composition of this name with his work detailed in the books entitled The Place-Names of Cardiganshire published by the British Archaeological Reports Oxford Ltd, and it is adjoined to the Mynydd Bach group of hills, which are situated in the western part of South Wales (Region B, Sub-Region B1), and it is positioned encircled by minor roads, with the B4577 road farther to its north, the B4337 road farther to its west, the B4342 road farther to its south and the B4576 road farther to its east, and has the town of Aberaeron 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 main P30 list with a summit height of 316m that appears as a spot height positioned at SN 562 615 on the contemporary Ordnance Survey 1:50,000 Landranger and 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 analysis gives the highest ground on this hill as 316.2m positioned at SN 56277 61518.  However, this is a part of a raised field boundary and protocols dictate that as this is deemed a relatively recent man-made construct such ground is discounted from the height of a hill. 

LIDAR summit image of Cymanfynydd Fach (SN 562 615)

The height produced by LIDAR analysis to the highest remaining natural ground of this hill is 315.6m positioned at SN 56285 61520, and this position in relation to the raised field boundary comes within the parameters of the Summit Relocations used within this page heading, these parameters are:

The term Summit Relocations applies when the high point of the hill is found to be positioned; in a different field, to a different feature such as in a conifer plantation,  within a different map contour, to a different point where a number of potential summit positions are within close proximity, when natural ground or the natural and intact summit of a hill is confirmed compared to a higher point such as a raised field boundary or covered reservoir that is considered a relatively recent man-made construct, or a relocation of approximately 100 metres or more in distance from either the position of a map spot height or from where the summit of the hill was previously thought to exist.

Therefore, the summit height produced by LIDAR analysis is 315.6m and this is positioned at SN 56285 61520, this position is close to where the 316m spot height appears on the contemporary Ordnance Survey 1:50,000 Landranger and the 1:25,000 Explorer map, and is approximately 8 metres eastward from where the high point of the raised field boundary is positioned. 

 

The full details for the hill are:

Group:  Mynydd Bach 

Name:  Cymanfynydd Fach 

OS 1:50,000 map:  146

Summit Height:  315.6m (LIDAR)                                                           

Summit Grid Reference (New Position):  SN 56285 61520 (LIDAR) 

Bwlch Height:  274.95m (LIDAR) 

Bwlch Grid Reference:  SN 55869 60212 (LIDAR) 

Drop:  40.7m (LIDAR) 

 

Myrddyn Phillips (December 2023)

 



Mapping Mountains - Summit Relocations - Y Trichant

Pt. 329.7m (SN 591 630) - 40th summit relocation

Hill Reclassifications post for Pt. 329.7m

Significant Height Revisions post for Pt. 329.7m

 

There has been a Summit Relocation to a hill that is listed in the 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. 329.7m (SN 591 630)

The criteria for the list that this summit relocation 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. 329.7m) notation and it is adjoined to the Mynydd Bach group of hills, which are situated in the western part of South Wales (Region B, Sub-Region B1), and it is positioned with the B4576 road to its north-west, B4577 road to its south and a minor road to its east, and has the village of Llangeitho towards the south-east.

When the original 300m height band of Welsh P30 hills were published on Geoff Crowder’s v-g.me website, this hill was not included in the Hills to be surveyed sub list, 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 327m summit height and an estimated c 307m bwlch height, with both heights based on interpolation of 5m contouring 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 and digitally updated such as the interactive mapping on the Magic Maps and WalkLakes websites.

One of the mapping resources now available online is on the Magic Maps website which hosts an interactive map originated from Ordnance Survey data.  Until recently this mapping had many spot heights not on other publicly available maps and for this hill it had a 327m spot height on the summit area of this hill and positioned at SN 59019 63010, resulting in its details being amended accordingly. 

Extract from the interactive mapping hosted on the Magic Maps website

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

LIDAR summit image of Pt. 329.7m (SN 591 630)

LIDAR analysis gives the highest ground on this hill as 329.7m positioned at SN 59108 63024, and this in relation to the previously listed summit position comes within the parameters of the Summit Relocations used within this page heading, these parameters are:

The term Summit Relocations applies when the high point of the hill is found to be positioned; in a different field, to a different feature such as in a conifer plantation,  within a different map contour, to a different point where a number of potential summit positions are within close proximity, when natural ground or the natural and intact summit of a hill is confirmed compared to a higher point such as a raised field boundary or covered reservoir that is considered a relatively recent man-made construct, or a relocation of approximately 100 metres or more in distance from either the position of a map spot height or from where the summit of the hill was previously thought to exist.

Therefore, the summit height produced by LIDAR analysis is 329.7m and this is positioned at SN 59108 63024, this position is not given a spot height on the contemporary Ordnance Survey 1:50,000 Landranger and the 1:25,000 Explorer map, and is approximately 90 metres eastward from where the previously listed summit is positioned which was based on the 327m spot height that appeared on the interactive mapping hosted on the Magic Maps website, and importantly the summit is positioned to a different feature. 

 

The full details for the hill are:

Group:  Mynydd Bach 

Name:  Pt. 329.7m 

OS 1:50,000 map:  146

Summit Height:  329.7m (LIDAR)                                                           

Summit Grid Reference (New Position):  SN 59108 63024 (LIDAR) 

Bwlch Height:  306.9m (LIDAR) 

Bwlch Grid Reference:  SN 59361 63409 & SN 59359 63413 (LIDAR) 

Drop:  22.8m (LIDAR) 

 

Myrddyn Phillips (November 2023)




Mapping Mountains - Summit Relocations - Y Trichant

Mynydd Llanfynydd (SN 545 286) - 39th summit relocation

Significant Name Changes post for Mynydd Llanfynydd

 

There has been a Summit Relocation to a hill that is listed in the 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 Llanfynydd (SN 545 286)

The criteria for the list that this summit relocation 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 Mynydd Llanfynydd and this was derived from the Tithe map, and it is adjoined to the Mynydd Mallaen 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 west and east, and the B4310 road to its north-west, and has the village of Brechfa 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 list with a summit height of 325m that appears as a spot height adjoined to a triangulation pillar positioned at SN 54623 28570 that appears on the Ordnance Survey 1:50,000 Landranger and 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 analysis gives the highest ground on this hill as 326.1m positioned at SN 54584 28615.  However, this is a part of a raised field boundary and protocols dictate that as this is deemed a relatively recent man-made construct such ground is discounted from the height of a hill. 

LIDAR summit image of Mynydd Llanfynydd (SN 545 286)

The height produced by LIDAR analysis to the natural summit of this hill is 325.6m positioned at SN 54561 28617, and this position in relation to the raised field boundary comes within the parameters of the Summit Relocations used within this page heading, these parameters are:

The term Summit Relocations applies when the high point of the hill is found to be positioned; in a different field, to a different feature such as in a conifer plantation,  within a different map contour, to a different point where a number of potential summit positions are within close proximity, when natural ground or the natural and intact summit of a hill is confirmed compared to a higher point such as a raised field boundary or covered reservoir that is considered a relatively recent man-made construct, or a relocation of approximately 100 metres or more in distance from either the position of a map spot height or from where the summit of the hill was previously thought to exist.

Therefore, the summit height produced by LIDAR analysis is 325.6m and this is positioned at SN 54561 28617, this position is not given a spot height on the contemporary Ordnance Survey 1:50,000 Landranger and the 1:25,000 Explorer map, and is approximately 23 metres eastward from where the high point of the raised field boundary is positioned and approximately 65 metres north-westward from where the triangulation pillar is positioned. 

 

The full details for the hill are:

Group:  Mynydd Mallaen 

Name:  Mynydd Llanfynydd 

OS 1:50,000 map:  146

Summit Height:  325.6m (LIDAR)                                                           

Summit Grid Reference (New Position):  SN 54561 28617 (LIDAR) 

Bwlch Height:  245.05m (LIDAR) 

Bwlch Grid Reference:  SN 57145 30251 (LIDAR) 

Drop:  80.5m (LIDAR) 

 

Myrddyn Phillips (September 2023)




Mapping Mountains - Summit Relocations - Y Trichant

Pen Llwyn Uchel (SN 517 387) - 38th summit relocation

Significant Height Revisions post for Pen Llwyn Uchel

Significant Name Changes post for Pen Llwyn Uchel

 

There has been a Summit Relocation to a hill that is listed in the 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 Pen Llwyn Uchel (SN 517 387)

The criteria for the list that this summit relocation 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 Pen Llwyn Uchel and it is adjoined to the Mynydd Pencarreg group of hills, which are situated in the south-western part of South Wales (Region B, Sub-Region B1), and it is positioned with a minor road to its immediate north, the A485 road to its west and the B4337 road to its east, and has the town of Llanybydder towards the north. 

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

When the original 300m height band of Welsh P30 hills were published on Geoff Crowder’s v-g.me website, this hill was included in the accompanying Hills to be surveyed sub list with a 381m summit height, based on the twin 381m spot heights that appear on the Ordnance Survey 1:25,000 Explorer map, with the prioritised summit positioned at SN 512 383 and with an accompanying note stating; Two tops of same height (SN517388 is 383m on 1985 1:50000 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. 

LIDAR summit image of Pen Llwyn Uchel (SN 517 387)

The summit height produced by LIDAR analysis is 383.45m positioned at SN 51750 38783 and SN 51757 38784, with LIDAR giving 380.7m positioned at SN 51229 38380 for the old prioritised summit, and this comes within the parameters of the Summit Relocations used within this page heading, these parameters are:

The term Summit Relocations applies when the high point of the hill is found to be positioned; in a different field, to a different feature such as in a conifer plantation,  within a different map contour, to a different point where a number of potential summit positions are within close proximity, when natural ground or the natural and intact summit of a hill is confirmed compared to a higher point such as a raised field boundary or covered reservoir that is considered a relatively recent man-made construct, or a relocation of approximately 100 metres or more in distance from either the position of a map spot height or from where the summit of the hill was previously thought to exist.

Therefore, the summit height produced by LIDAR analysis is 383.45m and this is positioned at SN 51750 38783 and SN 51757 38784, this position is given a 381m spot height on the contemporary Ordnance Survey 1:25,000 Explorer map and a 383m spot height on the contemporary Ordnance Survey 1:50,000 Landranger map, and is approximately 550 metres north-eastward from where the origin prioritised summit is positioned. 

 

The full details for the hill are:

Group:  Mynydd Pencarreg 

Name:  Pen Llwyn Uchel 

OS 1:50,000 map:  146

Summit Height:  383.45m (LIDAR)                                                           

Summit Grid Reference (New Position):  SN 51750 38783 & SN 51757 38784 (LIDAR) 

Bwlch Height:  359.6m (LIDAR) 

Bwlch Grid Reference:  SN 52370 38728 (LIDAR) 

Drop:  23.8m (LIDAR) 

 

Myrddyn Phillips (September 2023)

 



Mapping Mountains - Summit Relocations - Y Trichant

Tyn y Waun (SN 679 386) - 37th summit relocation

Significant Name Changes post for Tyn y Waun

 

There has been a Summit Relocation to a hill that is listed in the 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 Tyn y Waun (SN 679 386)

The criteria for the list that this summit relocation 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 Tyn y Waun and this was derived from the Tithe map, and it is adjoined to the Mynydd Mallaen 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 north, west and east, and the A482 road to its south, and has the town of Llanymddyfri (Llandovery) towards the east south-east.

When the original 300m height band of Welsh P30 hills were published on Geoff Crowder’s v-g.me website, this hill was included in the main P30 list with a 311m summit height, based on the spot height adjoined to a triangulation pillar that appears on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map and which is positioned at SN 67953 38615. 

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 summit image of Tyn y Waun (SN 679 386)

LIDAR analysis gives the highest ground on this hill as 311.5m positioned at SN 67956 38618.  However, this is a part of a raised field boundary and protocols dictate that as this is deemed a relatively recent man-made construct such ground is discounted from the height of a hill. 

LIDAR close up summit image of Tyn y Waun (SN 679 386)

The height produced by LIDAR analysis to the natural summit of this hill is 311.2m positioned at SN 67962 38620, and this position in relation to the raised field boundary comes within the parameters of the Summit Relocations used within this page heading, these parameters are:

The term Summit Relocations applies when the high point of the hill is found to be positioned; in a different field, to a different feature such as in a conifer plantation,  within a different map contour, to a different point where a number of potential summit positions are within close proximity, when natural ground or the natural and intact summit of a hill is confirmed compared to a higher point such as a raised field boundary or covered reservoir that is considered a relatively recent man-made construct, or a relocation of approximately 100 metres or more in distance from either the position of a map spot height or from where the summit of the hill was previously thought to exist.

Therefore, the summit height produced by LIDAR analysis is 311.2m and this is positioned at SN 67962 38620, this position is close to where the 311m spot height appears on the contemporary Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map, and is approximately six metres north-eastward from where the high point of the raised field boundary is positioned. 

 

The full details for the hill are:

Group:  Mynydd Mallaen 

Name:  Tyn y Waun 

OS 1:50,000 map:  146

Summit Height:  311.2m (LIDAR)                                                           

Summit Grid Reference (New Position):  SN 67962 38620 (LIDAR) 

Bwlch Height:  244.6m (LIDAR) 

Bwlch Grid Reference:  SN 68595 39591 (LIDAR) 

Drop:  66.6m (LIDAR) 

 

Myrddyn Phillips (September 2023)




Mapping Mountains - Summit Relocations - Y Trichant

Pant y Fyda (SN 562 361) - 36th summit relocation

Significant Name Changes post for Pant y Fyda

 

There has been a Summit Relocation to a hill that is listed in the 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 image of Pant y Fyda (SN 562 361)

The criteria for the list that this summit relocation 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 Pant y Fyda, and it is adjoined to the Mynydd Pencarreg group of hills, which are situated in the south-western part of South Wales (Region B, Sub-Region B1), and it is positioned with minor roads to its north and west, the B4310 road to its south-east and the B4337 road to its north-east, and has the village of Llansawel 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 main P30 list with a summit height of c 320m, which is the uppermost ring contour that appears on the Ordnance Survey 1:25,000 Explorer map and which is positioned at SN 56294 36161. 

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 analysis gives the highest ground on this hill as 322.1m positioned at SN 56283 36132 and SN 56286 36133.  However, this is a part of a raised water tank and protocols dictate that as this is deemed a relatively recent man-made construct such ground is discounted from the height of a hill. 

LIDAR summit image of Pant y Fyda (SN 562 361)

The height produced by LIDAR analysis to the natural summit of this hill is 321.4m positioned at SN 56293 36166, and this position in relation to the raised water tank comes within the parameters of the Summit Relocations used within this page heading, these parameters are:

The term Summit Relocations applies when the high point of the hill is found to be positioned; in a different field, to a different feature such as in a conifer plantation,  within a different map contour, to a different point where a number of potential summit positions are within close proximity, when natural ground or the natural and intact summit of a hill is confirmed compared to a higher point such as a raised field boundary or covered reservoir that is considered a relatively recent man-made construct, or a relocation of approximately 100 metres or more in distance from either the position of a map spot height or from where the summit of the hill was previously thought to exist.

Therefore, the summit height produced by LIDAR analysis is 321.4m and this is positioned at SN 56293 36166, this position is not given a spot height on the contemporary Ordnance Survey 1:50,000 Landranger and the 1:25,000 Explorer map, and is approximately 35 metres northward from where the high point of the raised water tank is positioned. 

 

The full details for the hill are:

Group:  Mynydd Pencarreg 

Name:  Pant y Fyda 

OS 1:50,000 map:  146

Summit Height:  321.4m (LIDAR)                                                           

Summit Grid Reference (New Position):  SN 56293 36166 (LIDAR) 

Bwlch Height:  c 287m (interpolation) 

Bwlch Grid Reference:  SN 55727 36635 (interpolation) 

Drop:  c 34m (LIDAR summit and interpolated bwlch) 

 

Myrddyn Phillips (August 2023)



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