Thursday, 5 November 2015

Mapping Mountains – Significant Height Revisions – 100m Twmpau


Bersham Bank (SJ 311 481) 

There has been a Significant Height Revision initiated by a survey with the Trimble GeoXH 6000 to a hill that is now listed in the 100m Twmpau (thirty welsh metre prominences and upward), with these details being retrospective as the survey that resulted in this height revision was conducted on 13th October 2015.  With the criteria for 100m Twmpau status being all Welsh hills at or above 100m and below 200m in height that have a minimum 30m of drop.

The name of the hill is Bersham Bank; with this being the preferred locally known name for the hill and which was given me when I made enquiries after my ascent (see Significant Name Changes).  There is no name for the hill on current maps but ‘Colliery (disused)’ appears on the Ordnance Survey 1:25,000 Explorer map where the hill is situated.  As the Ordnance Survey detail implies, this hill is the relic of coal waste which was deposited from the workings of the Bersham Colliery which closed its operations in December 1986.

Bersham Bank is situated in the Moel y Gamelin range of hills, and is positioned on the southern outskirts of Rhostyllen, which is a south-western suburb of Wrecsam (Wrexham).  There is a circuitous path on the southern and eastern middle section of the hill; this can be accessed from a road to its east that is adjacent to an industrial estate.  Beside the road is a perimeter fence seemingly barring entrance to a path on the lower slopes of the hill, however, one section of the six foot high fence has been toppled over giving access to the public, including local people, who I was told occasionally walk up the hill.

The hill had no classification prior to the survey with the Trimble GeoXH 6000 as although it is prominent and rises almost directly above the A 483; it possesses no contour rings on current Ordnance Survey maps, except for those at its bwlch and these are between 100m – 105m, with the height of the bwlch estimated as being c 103m, with the summit height produced by the survey with the Trimble GeoXH 6000 being 153.6m (converted to OSGM15).

Although this hill does not possess any summit contours on Ordnance Survey mapping, there are two hills created from coal waste that are relatively near to Bersham Bank that do possess separate ring contours, these are situated at SJ 311 469 and SJ 300 473. 

Therefore this hill’s new summit height is 153.6m (converted to OSGM15), as no summit contours exist for the hill this is a dramatic 48.6m increase in height compared to its uppermost hill to hill bwlch contour of 105m.


The full details for the hill are:

Cardinal Hill:  Moel y Gamelin

Summit Height (New Height):  153.6m (converted to OSGM15)

Name:  Bersham Bank

OS 1:50,000 map:  117

Summit Grid Reference:  SJ 31159 48116
   
Drop:  c 51m


Gathering data from the summit of Bersham Bank which resulted in this hill's significant height revision


Myrddyn Phillips (November 2015)





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