Mapping Mountains – Hill Reclassifications – The Welsh Highlands - Uchafion Cymru

Pt. 649.8m (SH 660 452) - Welsh Highland P15 reclassified to Welsh Highland Sub  

There has been a reclassification to the listing of the The Welsh Highlands – Uchafion Cymru, with the summit height, bwlch height and their locations, the drop and status of the hill derived from a Leica GS15 and automatic level and staff survey conducted by John Barnard, Graham Jackson and Myrddyn Phillips.

Pt. 649.8m (SH 660 452) on the right of photo with Moelwyn Mawr on the left towering over it

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 hill is being listed by the point (Pt. 649.8m) 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 and the A496 road to its east, and has the town of Blaenau Ffestiniog towards the east.

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

This hill was included in the original list of Welsh 500m P15s that later became known as Yr Uchafion and latterly as The Welsh Highlands – Uchafion Cymru and listed with 15m of drop, based on a series of Basic Levelling Surveys (BLS) conducted by Myrddyn Phillips in 1998.  The results were forwarded to John and Anne Nuttall for their 2,000ft Welsh list of mountains.  When accepted into the Nuttalls list John and Anne coined the name Moelwyn Mawr North Ridge Top for this hill.  

However,  its marginal status meant that it was always a prime candidate for being accurately surveyed.  This was subsequently done using two methods:  a line survey; the more accurate technique and a GNSS survey using a Leica GS15 and a Trimble GeoXH 6000.

Therefore, the reclassification of this hill to Welsh Highland Sub status is due to an automatic level and staff line survey and a Leica GS15 survey, resulting in a 649.8m summit height and a 635.0m bwlch height, with these values giving this hill 14.8m of drop, which is insufficient for it to be classified as a Welsh Highland P15. 

The full details for the hill are:

Group:  Moelwyn Mawr

Name:  Pt. 649.8m

OS 1:50,000 map:  115

Summit Height:  649.8m (converted to OSGM15, Leica GS15)

Summit Grid Reference:  SH 66096 45255 (Leica GS15 and Trimble GeoXH 6000)

Bwlch Height:  635.0m (converted to OSGM15, Leica GS15)

Bwlch Grid Reference:  SH 66085 45195 (Leica GS15 and Trimble GeoXH 6000)

Drop:  14.8m (Leica GS15 and line survey)

Myrddyn Phillips and Aled Williams (June 2015)