Mapping Mountains – Hill Reclassifications – The Welsh P15s

 

Comin Gwauncaegurwen (SN 711 123) – Welsh P15 addition 

There has been an addition to the list of 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 Comin Gwauncaegurwen (SN 711 123)

The criteria for the list that this addition 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 Comin Gwauncaegurwen and this was derived from the Tithe map with the language protocol also used, 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 the A4068 road to its north-east, the A4069 road to its north-west and a minor road to its south, and has the village of Brynaman towards the north.

When the listing that became known as The Welsh P15s was being compiled, this hill was not included in the main P15 list or the accompanying P14 sub list, as with no significant contours of note on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map it was difficult to know whether any hill of note existed. 

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

One of the mapping resources now available online is the WalkLakes website which hosts an interactive map originated from the Ordnance Survey Open Data programme.  This map has many spot heights not on other publicly available maps and a 216m spot height is given on the summit area of this hill. 

Extract from the interactive mapping hosted on the WalkLakes website

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

Therefore, the addition of this hill to Welsh P15 status is due to LIDAR analysis, resulting in a 216.6m summit height and a 196.6m bwlch height, with these values giving this hill 19.98m of drop, which is sufficient for it to be included in the main list of The Welsh P15s. 

 

The full details for the hill are: 

Group:  Mynydd Du 

Name:  Comin Gawuncaegurwen 

OS 1:50,000 map:  160

Summit Height:  216.6 (LIDAR)                                                           

Summit Grid Reference:  SN 71158 12343 (LIDAR) 

Bwlch Height:  196.6m (LIDAR) 

Bwlch Grid Reference:  SN 71330 12592 & SN 71332 12592 (LIDAR) 

Drop:  19.98m (LIDAR) 

 

Myrddyn Phillips (April 2024)