Mapping Mountains – Hill Reclassifications – Welsh Highlands – Uchafion Cymru

Foel Fach (SH 944 423) – 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 for the Welsh Highlands – Uchafion Cymru list authored by Aled Williams and Myrddyn Phillips. 

LIDAR image of Foel Fach (SH 944 423)

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 Myrddyn Phillips and Aled Williams

The name the hill is listed by is Foel Fach and it is adjoined to the Carnedd y Filiast group of hills, which are situated in the central part of North Wales (Region A, Sub-Region A2), and it is positioned with the B4501 road to its north-west, the A4212 road to its south-west, the A494 road to its south-east and the A5 road to its north-east, and has the town of Y Bala towards the south.

This hill was not included in the initial P10 sub list when it was completed in June 2020 as with a 544m summit height and an estimated c 536m bwlch height, based on enlarged scale Ordnance Survey mapping available online, these values gave this hill an estimated c 8m of drop. 

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 addition of this hill to Welsh Highland Sub status is due to LIDAR analysis, resulting in a 544.5m summit height and a 534.4m bwlch height, with these values giving this hill 10.1m of drop, which is sufficient for it to be classified as a Welsh Highland Sub. 

 

The full details for the hill are: 

Group:  Carnedd y Filiast

Name:  Foel Fach

OS 1:50,000 map:  125

Summit Height:  544.5m (LIDAR)

Summit Grid Reference:  SH 94433 42381 (LIDAR)

Bwlch Height:  534.4m (LIDAR)

Bwlch Grid Reference:  SH 94485 42417 (LIDAR)   

Drop:  10.1m (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 (May 2023)