Tuesday, 7 March 2017

Mapping Mountains – Hill Reclassifications – Y Trechol – The Dominant Hills of Wales

Castell Cricieth (SH 500 377) - Dominant addition

There has been an addition to the listing of Y Trechol – The Dominant Hills of Wales due to detail included on the Ordnance Survey enlarged mapping hosted on the Geograph website and which was first spotted by Alex Cameron.  This has resulted in the hill being added to the Dominant list.  With the criteria for inclusion to this list being those Welsh P30 hills whose prominence equal or exceed half that of their absolute height.

The details relating to this hill’s inclusion as a Dominant hill are retrospective as it was added to the list shortly after Alex first proposed it as a new P30 in September 2014, and later appeared in the Moel Hebog group of hills when published on Mapping Mountains on the 28th January 2016.

Prior to Alex Cameron proposing this hill as a new P30 and its subsequent inclusion as a Dominant hill it had remained unclassified, as the Ordnance Survey 1:50,000 Landranger map and 1:25,000 Explorer map has an uppermost contour of 30m and bwlch contouring between 10m – 20m, which implied that this hill did not have the required 30m of drop to be considered for Dominant status.

The hill is in the Moel Hebog group of hills and is placed in the Region of North Wales (Region A, Sub-Region A1) and is situated in the heartland of the town of Cricieth overlooking the sea, which is to its immediate east and south.

The name of the hill is taken from the castle at its top; Castell Cricieth,  and there is an admittance fee for those wishing to visit, it was included as a Dominant hill as the Ordnance Survey enlarged map hosted on the Geograph website has contours at 5m intervals giving the hill an uppermost contour of 45m and a summit spot height of 48m, with bwlch contouring between 15m – 20m, with an estimated bwlch of c 18m, giving the hill an estimated drop of c 30m and 62.5% Dominance.  The hill has subsequently been surveyed with the Trimble GeoXH 6000 with a summit height of 49.6m (converted to OSGM15) and a bwlch height of 19.3m (converted to OSGM15), with these values giving the hill 30.3m of drop and 61.02% Dominance.

The full details for the hill are:

Group:  Moel Hebog

Name:  Castell Cricieth

Dominance:  61.02%

OS 1:50,000 map:  123

Summit Grid Reference:  SH 50003 37733

Summit Height:  49.6m (converted to OSGM15)

Drop Summit to Bwlch:  30.3m

Drop Bwlch to ODN:  19.3m (converted to OSGM15) 

Castell Cricieth (SH 500 377) confirmed as a Dominant hill

Myrddyn Phillips (March 2017)

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