Mapping Mountains – Hill Reclassifications – Y Pedwarau

Bryn Glas (SH 735 420) - 400m Sub-Pedwar addition

There has been a new 400m Sub-Pedwar recently discovered by map study.  The hill is situated just to the south of Llyn Morwynion (SH 737 423) amongst those hills that are positioned between the eastern Moelwynion and the north-western Arenig.  It’s inclusion as a 400m Sub-Pedwar was later confirmed by a survey with the Trimble GeoXH 6000.

The name of the hill is Bryn Glas and it was added to the ranks of 400m Sub-Pedwar hills based on the 416m summit spot height on the Ordnance Survey enlarged mapping on the Geograph website, whilst the c 395m bwlch height has been estimated from contour interpolation, these values gave the hill c 21m of drop.  The later Trimble survey resulted in a 415.6m (converted to OSGM15) summit height and a 393.9m (converted to OSGM15) bwlch height, giving this hill 21.7m of drop and confirming its addition as a 400m Sub-Pedwar.

The hill will be added to the Y Pedwarau list in the 2^nd edition that will hopefully be published by Europeaklist.  The list of Pedwar hills is also available from the Haroldstreet website.

The full details for the hill are:

Cardinal Hill:  Graig Goch

Summit Height:  415.6m (converted to OSGM15)

Name:  Bryn Glas

OS 1:50,000 map:  124

Summit Grid Reference:  SH 73505 42086

Drop:  21.7m (converted to OSGM15)

Bryn Glas (SH 735 420) confirmed as a 400m Sub-Pedwar

For details on the survey that confirmed this hill as a 400m Sub-Pedwar please click {here}

Myrddyn Phillips and Aled Williams (April 2014)