Mapping Mountains – Significant Name Changes – 30-99m Twmpau, Y Trechol – The Dominant Hills of Wales and Y Pellennig – The Remotest Hills of Wales

Skomer (SM 726 094) 

There has been a Significant Name Change that is retrospective to a hill that is listed in the 30-99m Twmpau, Y Trechol – The Dominant Hills of Wales and Y Pellennig – The Remotest Hills of Wales, with the summit height and its location, the drop, dominance and status of the hill derived from LIDAR analysis conducted by Myrddyn Phillips.                       

LIDAR image of Skomer (SM 726 094)

The criteria for the three listings 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

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 3^rd 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

Y Pellennig – The Remotest Hills of Wales - Welsh hills whose summit is at least 2.5km from the nearest paved public road and the hill has 15m minimum drop.  The list is co-authored by Myrddyn Phillips and Aled Williams and is available as a downloadable e-booklet and print-booklet version on Mapping Mountains Publications with the up-to-date master list available to download on the Mapping Mountains site in Google Doc format.

Y Pellennig - The Remotest Hills of Wales by Myrddyn Phillips and Aled Williams

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, and has the town of Hwlffordd (Haverfordwest) 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 Gorse Hill, which is a prominent name that appears to the south of the summit 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 Gorse Hill was also used for this hill. 

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

The listed name of this hill was subsequently revised to Pt. 79m, Skomer when the 1^st edition of the Y Pellennig – The Remotest Hills of Wales was published by Europeaklist in April 2015.  With the point notation used to differentiate hills of the same name.  For hills such as this, the point notation protocol has now been dropped in favour of just using the main name.

Therefore, the name this hill is now listed by in the 30-99m Twmpau, Y Trechol – The Dominant Hills of Wales and Y Pellennig – The Remotest Hills of Wales is Skomer, and this was derived from a variety of different scaled Ordnance Survey maps. 

 

The full details for the hill are:

Group:  Garn Fawr

Name:  Skomer 

Previously Listed Name:  Gorse Hill (originally listed), Pt. 79m, Skomer (previously listed)   

OS 1:50,000 map:  157

Summit Height:  79.3m (LIDAR) 

Summit Grid Reference:  SM 72695 09460 (LIDAR)               

Bwlch Height:  N/A (sea level) 

Bwlch Grid Reference:  N/A (sea level) 

Drop:  79.3m (LIDAR) 

Dominance:  100.00% (LIDAR) 

Remoteness:  3.410km 

 

Myrddyn Phillips and Aled Williams (October 2025)