Friday, 10 July 2015

Mapping Mountains – Summit Relocations – Y Pedwarau

Pt. 430.7m (SO 089 525)

There has been a Summit Relocation to the listing of the Y Pedwarau instigated from a survey with the Trimble GeoXH 6000.  The Y Pedwarau takes in all the 400m hills of Wales that have a minimum 30m of drop, and the following details are retrospective as the survey that resulted in this summit relocation was conducted on 25th April 2015.

The survey with the Trimble was conducted in the Fforest Glud hills to the south-west of Hundred House, which is a small community to the north-east of Llanfair-ym-Muallt (Builth Wells) in the heartland of Mid-Wales.

This hill formed part of a circuit around Aberedw Hill (SO 084 507) in the company of Mark Trengove and Aled Williams who were visiting hills whilst I scampered ahead to survey them.  The culmination of the walk was on the summit of Aberedw Hill where we met Carole Engel, Anton Ciritis, Alex Cameron and Alan Greenwood to celebrate Carole’s completion of the Y Pedwarau – The 400m Hills of Wales.

The hill is listed as a Pedwar and remains unnamed on current Ordnance Survey maps and  as we currently do not know an appropriate name for it either from local enquiry or from historical research it is being listed under the point (Pt. 430.7m) notation.

The summit area of the hill has three small 430m ring contours on Odnance Survey maps, with the furthest easterly one being given a spot height of 432m, and this is where the summit of the hill used to be listed.

The position of each of these contour rings was surveyed with the Trimble resulting in:

Summit 1:  429.8m (converted to OSGM15) at SO 09189 52379

Summit 2:  430.7m (converted to OSGM15) at SO 08911 52554

Summit 3:  428.9m (converted to OSGM15) at SO 08099 52175

Summit 1 is where the 432m spot height appears on current Ordnance Survey maps, but its adjacent summit (Summit 2) was surveyed with the Trimble as being 0.8m higher

The new summit position for this hill is approximately 320 metres north-westward from where the 432m spot height appears on the ground.

The full details for the hill are:

Cardinal Hill:  Great Rhos

Summit Height:  430.7m (converted to OSGM15)

Name:  Pt. 430.7m

OS 1:50,000 map:  147

Summit Grid Reference (New Position):  SO 08911 52554 
Drop:  30.1m (converted to OSGM15)

The Trimble GeoXH 6000 gathering data at the new summit position of Pt. 430.7m, with the old position of the summit in centre background of this photo

For details on the survey that relocated the summit of this hill please click {here}

Myrddyn Phillips and Aled Williams (April 2015)

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