Mapping Mountains – Hill Reclassifications – Welsh Highlands – Uchafion Cymru

Pt. 524.3m (SH 661 457) – 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 a Trimble GeoXH 6000 survey conducted by Aled Williams. 

Pt. 524.3m (SH 661 457) (Photo: Aled Williams)

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 hill is being listed by the point (Pt. 524.3m) notation and it is adjoined to the Moelwyn Mawr group of hills, which are situated in the north-western part of North Wales (Region A, Sub-Region A2), and it is positioned with the A4085 road to its west, the A487 road to its south and the A496 road to its south-east, and has the town of Blaenau Ffestiniog towards the east. 

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

When the initial P10 sub list was completed in June 2020 this hill was not included, as the contemporary Ordnance Survey 1:25,000 Explorer map only has two small uppermost 520m contours without any summit or bwlch spot height.

However, the hill was surveyed by Aled Williams using the Trimble GeoXH 6000.  Upon investigation it was judged that the natural drop of this hill exceeds 10m, with the area of the bwlch complicated by a dam and leat.  The conclusion being that the natural bwlch was either under the dam or further north past the leat, but for now we are taking the bottom of the dam as the critical point of the bwlch.

The Trimle GeoXH 6000 gathering data at the summit of Pt. 524.3m (SH 661 457) (Photo: Aled Williams)

Looking down at the bwlch (Photo: Aled Williams)

Therefore, the addition of this hill to Welsh Highland Sub status is due to a Trimble GeoXH 6000 survey, resulting in a 524.3m summit height and a 513.5m bwlch height, with these values giving this hill 10.7m of drop, which is sufficient for it to be classified as a Welsh Highland Sub. 

 

The full details for the hill are: 

Group:  Moelwyn Mawr

Name:  Pt. 524.3m

OS 1:50,000 map:  124

Summit Height:  524.3m (converted to OSGM15)

Summit Grid Reference:  SH 66117 45783

Bwlch Height:  513.5m (converted to OSGM15)

Bwlch Grid Reference:  SH 66131 45774   

Drop:  10.7m 

 

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 (April 2023)