Mapping Mountains – Hill Reclassifications – Welsh Highlands – Uchafion Cymru

 

Llechwedd Crin (SN 813 922) – Welsh Highland Sub addition 

There has been an addition to the listing of the Welsh Highlands – Uchafion Cymru, with the summit height, bwlch height and their locations, the drop and status of the hill derived from LIDAR analysis conducted by Aled Williams. 

LIDAR image of Llechwedd Crin (SN 813 922)

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

Welsh Highlands – Uchafion Cymru – Welsh hills at or above 500m in height with 15m minimum drop, with an accompanying sub list entitled the Welsh Highland Subs, the criteria for which is all Welsh hills at or above 500m in height with 10m or more and below 15m of drop.  This list is authored by Myrddyn Phillips and Aled Williams with the Introduction to the list published on Mapping Mountains in November 2015 and the latest update relating to the list published on Mapping Mountains in January 2023.

Welsh Highlands - Uchafion Cymru by Aled Williams and Myrddyn Phillips

The name the hill is listed by is Llechwedd Crin and it is adjoined to the Pumlumon group of hills, which are situated in the northern part of South Wales (Region B, Sub-Region B1), and it is positioned with a minor road to its north-east and its south-west, the B4518 road to its east and the A44 road to its south, and has the village of Penffordd-las (Staylittle) towards the east. 

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

After the original list that later became known as the Welsh Highlands – Uchafion Cymru was first compiled, this hill was listed with an estimated c 10m of drop, based on partial LIDAR coverage giving a 536m summit height and a 526m bwlch height.

When the details for this hill were updated with data from basic levelling surveys conducted by Myrddyn Phillips, the drop was amended to below 10m, based on a 31½ft/9.6m basic levelling survey conducted on the 22.05.04.

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 Highland Sub status is due to LIDAR analysis, resulting in a 536.2m summit height and a 525.6m bwlch height, with these values giving this hill 10.6m of drop, which is sufficient for it to be classified as a Welsh Highland Sub. 

 

The full details for the hill are: 

Group:  Pumlumon

Name:  Llechwedd Crin

OS 1:50,000 map:  135, 136

Summit Height:  536.2m (LIDAR)

Summit Grid Reference:  SN 81384 92266 (LIDAR)

Bwlch Height:  525.6m (LIDAR)

Bwlch Grid Reference:  SN 81539 92254 (LIDAR)   

Drop:  10.6m (LIDAR) 

 

For the additions, deletions and reclassifications to the Welsh Highlands – Uchafion Cymru reported on Mapping Mountains please consult the following Change Registers:

 

Welsh Highland P15s

 

Welsh Highland Subs

 

Aled Williams and Myrddyn Phillips (December 2023)