Friday, 16 June 2023

Mapping Mountains – Hill Reclassifications – Welsh Highlands – Uchafion Cymru


Pt. 585.6m (SJ 130 326) – Welsh Highland P15 reclassified to Welsh Highland Sub 

There has been a reclassification to the listing of the Welsh Highlands – Uchafion Cymru, with the summit height, bwlch height and their locations, the drop and status of the hill derived from LIDAR analysis conducted by Aled Williams. 

LIDAR image of Pt. 585.6m (SJ 130 326)

The criteria for the list that this reclassification applies to are:

Welsh Highlands – Uchafion Cymru Welsh hills at or above 500m in height with 15m minimum drop, with an accompanying sub list entitled the Welsh Highland Subs, the criteria for which is all Welsh hills at or above 500m in height with 10m or more and below 15m of drop.  This list is authored by Myrddyn Phillips and Aled Williams with the Introduction to the list published on Mapping Mountains in November 2015 and the latest update relating to the list published on Mapping Mountains in January 2023.

Welsh Highlands - Uchafion Cymru by Myrddyn Phillips and Aled Williams

The hill is being listed by the point (Pt. 585.6m) notation, and it is adjoined to the Craig Berwyn group of hills, which are situated in the eastern part of North Wales (Region A, Sub-Region A3), and it is positioned with a minor road to its north-east and south, and the B4500 road to its east north-east, and has the village of Llanarmon Dyffryn Ceiriog towards the east.

When the original list that later became known as the Welsh Highlands – Uchafion Cymru was first compiled, this hill was included as a Welsh Highland P15 and listed with 15m of drop, based on the 587m summit spot height and 572m bwlch spot height that appear on the Ordnance Survey 1:25,000 Explorer map. 

Extract from the Ordnance Survey 1:25,000 Explorer map

However, it was not until LIDAR became available that the details for this hill could be accurately re-assessed.  The LIDAR (Light Detection & Ranging) technique produced highly accurate height data that is now freely available for much of England and Wales.

Therefore, the reclassification of this to Welsh Highland Sub status is due to LIDAR analysis, resulting in a 585.6m summit height and a 571.5m bwlch height, with these values giving this hill 14.15m of drop, which is insufficient for it to be classified as a Welsh Highland P15. 

 

The full details for the hill are: 

Group:  Craig Berwyn

Name:  Pt. 585.6m

OS 1:50,000 map:  125

Summit Height:  585.6m (LIDAR)

Summit Grid Reference:  SJ 13031 32635 (LIDAR)

Bwlch Height:  571.5m (LIDAR)

Bwlch Grid Reference:  SJ 12920 32539 (LIDAR)   

Drop:  14.15m (LIDAR) 

 

For the additions, deletions and reclassifications to the Welsh Highlands – Uchafion Cymru reported on Mapping Mountains please consult the following Change Registers:

 

Welsh Highland P15s

 

Welsh Highland Subs

 

Aled Williams and Myrddyn Phillips (June 2023)

 

 

  

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