Mapping Mountains – Summit Relocations – The Welsh P15s

Mynydd Cribau (SN 759 552) 

There has been a Summit Relocation to a hill that is listed in the The Welsh P15s, 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 Cribau (SH 759 552)

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

The Welsh P15s – Welsh hills with 15m minimum drop, irrespective of their height, with an accompanying sub list entitled the Welsh Sub-P15s, with the criteria for this sub category being all Welsh hills with 14m or more and below 15m of drop.  The list is authored by Myrddyn Phillips, with the Introduction to the list appearing on Mapping Mountains on the 10^th May 2019. 

The Welsh P15s by Myrddyn Phillips

The name the hill is listed by is Mynydd Cribau, and it is adjoined to the Moel Siabod group of hills, which are situated in the north-western part of North Wales (Region A, Sub-Region A1), and it is positioned with the A5 road to its north and east, and the A470 road to its south, and has the village of Betws-y-coed towards the east north-east.

When the listing that became known as The Welsh P15s was being compiled, this hill was included in the accompanying P14 sub list with an estimated c 14m of drop, based on the 322m summit spot height positioned at SH 75790 55014 that appeared on the Ordnance Survey Vector Map Local hosted on the Geograph website and which was entitled the Interactive Coverage Map and an estimated c 308m 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 summit image of Mynydd Cribau (SH 759 552)

The height produced by LIDAR analysis to the summit of this hill is 322.0m and is positioned at SH 75985 55229, whilst LIDAR gives the highest ground adjacent to where the 322m spot height appeared as 320.9m positioned at SH 75788 55018, 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 either on Ordnance Survey maps or interactive mapping, 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 the listing of a new twin summit or de-twinning of a summit, 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 322.0m and this is positioned at SH 75985 55229.  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 210 metres north-eastward from where the highest ground adjacent to the 322m spot height appeared on the Ordnance Survey Vector Map Local hosted on the Geograph website and which was entitled the Interactive Coverage Map. 

 

The full details for the hill are: 

Group:  Moel Siabod 

Name:  Mynydd Cribau 

OS 1:50,000 map:  115

Summit Height:  322.0m (LIDAR)                                                           

Summit Grid Reference (New Position):  SH 75985 55229 (LIDAR)                                                  

Bwlch Height:  308.0m (LIDAR) 

Bwlch Grid Reference:  SH 76100 55557 (LIDAR) 

Drop:  14.05m (LIDAR) 

 

Myrddyn Phillips (August 2026)

  

Monthly Synopsis

 

Synopsis of all major changes detailed on Mapping Mountains during the last calendar month.  These can include new, confirmation and retrospective changes

 

Hill Reclassifications: 

Almsworthy Common (SS 841 420) - Sub-Four exclusion

Little Buscombe (SS 767 424) - Sub-four exclusion

 

Significant Height Revisions: 

Mynydd Nodol (SH 865 393) - 500m Twmpau and The Welsh Highlands - Uchafion Cymru

Rhobell Ganol (SH 785 274) - The Deweys

Summit Relocations: 

Troed Rhiw Bylchau (SN 761 471) - Y Trichant - The 300m Hills of Wales

Significant Name Changes: 

Mynydd Deulyn (SH 754 605) - The Welsh P15s

Gaer Fawr (SJ 223 129) - 200m Twmpau and Y Trechol - The Dominant Hills of Wales

Cae Gwyn (SH 762 585) - The Welsh P15s

Emsger (SM 651 226) - 30-99m Twmpau

Mapping Mountains – Significant Name Changes – 30-99m Twmpau

Emsger (SM 651 226) 

There has been a Significant Name Change that is retrospective to a hill that is listed in the 30-99m Twmpau, with the summit height and its location, the drop and status of the hill derived from a Trimble GeoXH 6000 survey conducted by Myrddyn Phillips.                       

Emsger (SM 651 226)

The criteria for the list that this name change applies to are:

30-99m Twmpau - Welsh hills at or above 30m and below 100m in height that have 30m minimum drop, with an accompanying sub list entitled the 30-99m Sub-Twmpau, with the criteria for this sub category being all Welsh hills at or above 30m and below 100m in height with 20m or more and below 30m of drop.  The list is authored by Myrddyn Phillips, with the word Twmpau being an acronym standing for thirty welsh metre prominences and upward. 

30-99m Twmpau by Myrddyn Phillips

The hill is adjoined to the Garn Fawr group of hills, which are situated in the south-western part of South Wales (Region B, Sub-Region B1), and it is positioned with the nearest minor road on the mainland to its east north-east, and has the city of Tyddewi (St David’s) on the mainland towards the east north-east.

When the original 30-99m height band of Welsh P30 hills compiled by Myrddyn Phillips were published on Geoff Crowder’s v-g.me website, this hill appeared under the transposed name of Em-sger or South Bishop, which is a prominent name that appears adjacent to this island on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map.  Soon afterward Myrddyn Phillips compiled the dominant and remote listings, and in these original compilations the name of Emsger was prioritised. 

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

Both names are applicable to the same island, with South Bishop originating from English and Emsger probably originating from Old Norse, with the latter documented in 1717  incorporating a Welsh word as Carreg Emskar (Dictionary of the Place-Names of Wales by Hywel Wyn Owen and Richard Morgan and published by Gomer Press in 2007).

Therefore, the prioritised name this hill is now listed by in the 30-99m Twmpau is Emsger, and this was derived from a variety of sources, including the contemporary Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map. 

 

The full details for the hill are:

Group:  Garn Fawr

Name:  Emsger 

Previously Listed Name:  Em-sger or South Bishop   

OS 1:50,000 map:  157

Summit Height:  33.8m (converted to OSGM15, Trimble GeoXH 6000) 

Summit Grid Reference:  SM 65116 22619               

Bwlch Height:  N/A (sea level) 

Bwlch Grid Reference:  N/A (sea level) 

Drop:  33.8m (Trimble GeoXH 6000) 

 

Myrddyn Phillips (July 2026) 

Mapping Mountains – Hill Reclassifications – The Fours – The 400m Hills of England

 

Little Buscombe (SS 767 424) – Sub-Four exclusion

There has been an exclusion from the listing of the The Fours – The 400m Hills of England, with the summit height, col height and their locations, the drop and status of the hill derived from LIDAR analysis conducted by Myrddyn Phillips. 

LIDAR image of Little Buscombe (SS 767 424)

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

The Fours – The 400m Hills of England - English hills at or above 400m and below 500m in height that have 30m minimum drop, accompanying the main list is a sub list entitled the Sub-Fours, the criteria for which are all English hills at or above 400m and below 500m in height that have 15m or more and below 30m of drop.  The list is co-authored by Myrddyn Phillips and Aled Williams and is available to download in Google Doc format from the Mapping Mountains site.

The Fours - The 400m Hills of England by Myrddyn Phillips and Aled Williams

The name the hill is listed by is Little Buscombe, and it is adjoined to the Dunkery Beacon group of hills, which are situated in the counties of Somerset and Devon, and it is positioned with the the B3223 road to its west and the B3358 road to its south, and has the village of Simonsbath towards the south.

When the Introduction to the first group of hills for the updated and revised listing of the The Fours – The 400m Hills of England was published by Mapping Mountains on the 10^th September 2022, it was announced that the accompanying sub lists were being revised with the two 390m categories dispensed with and the criteria and name of the 400m Sub-Fours revised.  The one accompanying sub list is now named the Sub-Fours with its criteria being all English hills 400m and above and below 500m in height that have 15m and more and below 30m of drop.

Prior to this revision this hill was listed with 15m of drop, based on the 449m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and the 434m col 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.

Therefore, the exclusion of this hill from Sub-Four status is due to LIDAR analysis, resulting in a 448.9m summit height and a 434.1m col height, with these values giving this hill 14.8m of drop, which is insufficient for it to be classified as a Sub-Four. 

 

The full details for the hill are:

Group:  Dunkery Beacon

Name:  Little Buscombe

OS 1:50,000 map:  180

Summit Height:  448.9m (LIDAR)

Summit Grid Reference:  SS 76767 42409 (LIDAR)

Col Height:  434.1m (LIDAR)

Col Grid Reference:  SS 76309 42059 (LIDAR)

Drop:  14.8m (LIDAR)

 

For the additions, deletions and reclassifications to The Fours – The 400m Hills of England reported on Mapping Mountains since the December 2013 publication of the 1^st edition of this list by Europeaklist please consult the following Change Registers:

 

The Fours

 

Sub-Fours

 

Myrddyn Phillips and Aled Williams (July 2026)              

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

 

Troed Rhiw Bylchau (SN 761 471) 

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 Troed Rhiw Bylchau (SN 761 471)

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 13^th May 2017, and the Introduction to the Mapping Mountains publication of the list appearing on the 1^st January 2022. 

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

The name the hill is listed by is Troed Rhiw Bylchau, and it is adjoined to the Esgair Wen 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-east and south-west, and has the town of Llanwrtyd towards the east.

When the original 300m height band of Welsh P30 hills were published on Geoff Crowder’s v-g.me website, this hill was not included in the accompanying 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 19m of drop, based on the 383m summit spot height positioned at SN 75901 47064 that appears on the Ordnance Survey 1:25,000 Explorer map and the 364m 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 summit image of Troed Rhiw Bylchau (SN 761 471)

The summit height produced by LIDAR analysis is 387.8m and is positioned at SN 76197 47177, as opposed to 382.0m positioned in the vicinity of the spot height at SN 75899 47064, and this comes within 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 either on Ordnance Survey maps or interactive mapping, 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 the listing of a new twin summit or de-twinning of a summit, 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 387.8m and this is positioned at SN 76197 47177.  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 200 metres east north-eastward from where the 383m spot height and the previously listed summit is positioned. 

 

The full details for the hill are: 

Group:  Esgair Wen 

Name:  Troed Rhiw Bylchau 

OS 1:50,000 map:  146, 147

Summit Height:  387.8m (LIDAR)                                                           

Summit Grid Reference (New Position):  SN 76197 47177 (LIDAR) 

Bwlch Height:  360.6m (LIDAR) 

Bwlch Grid Reference:  SN 76205 47017 & SN 76217 47008 (LIDAR) 

Drop:  27.1m (LIDAR) 

 

Myrddyn Phillips (July 2026)