Wednesday, 26 July 2017

Mapping Mountains – Hill Reclassifications – Y Trichant


Commins (SJ 174 282) – Sub-Trichant reclassified to Trichant

There has been a confirmation of a reclassification to the listing of Y Trichant due to a survey with the Trimble GeoXH 6000.  Y Trichant is the title for the hills in the 300m height band of the Twmpau (thirty welsh metre prominences and upward) and takes in all Welsh hills at or above 300m and below 400m in height that have a minimum 30m of drop, with the introduction to the re-naming of this list appearing on Mapping Mountains on the 13th May 2017.

The hill was listed in the sub category that accompanied the original Welsh P30 lists when published on Geoff Crowder’s v-g.me website, this sub category has now been standardised and named the Sub-Trichant and comprises all Welsh hills at or above 300m and below 400m in height with 20m or more and below 30m of drop.

When the sub list was standardised and drop values also added the hill was reclassified to the main Y Trichant list with c 31m of drop which was later amended to c 34m of drop, based on the 376m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and an estimated bwlch height of c 342m based on interpolation of bwlch contours between 340m – 350m.

The name of the hill is Commins which was derived from local enquiry and it is situated in the  Y Berwyn group of hills and is placed in the Region of North Wales (Region A, Sub-Region A4) with its Cardinal Hill being Craig Berwyn (SJ 071 323).  The hill is positioned above the small communities of Moelfre which is to its east north-east and Llansilin which is farther away to the hill’s east.

As the hill is not a part of designated open access land, permission to visit should be sought, for those wishing to do so an ascent on public footpaths either from the west or east connects with green tracks which ascend toward the summit.

The survey with the Trimble produced a summit height of 376.1m (converted to OSGM15) and a bwlch height of 341.4m (converted to OSGM15), with these values giving this hill 34.7m of drop, which confirms its reclassification to Trichant status and the total in the Y Trichant and the Twmpau will be updated accordingly.


The full details for the hill are:


Cardinal Hill:  Craig Berwyn

Summit Height:  376.1m (converted to OSGM15)

Name:  Commins

OS 1:50,000 map:  125

Summit Grid Reference:  SJ 17476 28210 
  
Drop:  34.7m (converted to OSGM15)



Commins (SH 174 282) on left of photograph


Myrddyn Phillips (July 2017)


No comments: