Yr Esgair (SH 629 613) – Welsh Highland
Sub deletion
There has been a deletion 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 Yr Esgair (SH 629 613) |
The criteria for the list that this deletion applies to are:
|
Welsh Highlands - Uchafion Cymru by Myrddyn Phillips and Aled Williams |
The name the hill is listed by is Yr Esgair and it
is adjoined to the Glyder Fawr group of hills, which are situated in the north-western part of North Wales (Region A,
Sub-Region A1), and it is positioned with the A4086
road to its south-west and the A5 road to its east, and has the town of
Besethda towards the north.
When the initial P10 sub list was completed in
June 2020 this hill was listed with an estimated c 10m of drop, based on a 708m
summit height and an estimated c 698m bwlch height, and therefore included as a
Welsh Highland Sub when the drop value of the subs was agreed upon and revised
in July 2020.
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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 deletion of this hill from Welsh
Highland Sub status is due to LIDAR analysis, resulting in a 708.3m summit
height and a 702.0m bwlch height, with these values giving this hill 6.3m of
drop, which is insufficient for it to be classified as a Welsh Highland
Sub.
The full details for the hill are:
Group: Glyder Fawr
Name: Yr Esgair
OS 1:50,000 map: 115
Summit Height: 708.3m
(LIDAR)
Summit Grid Reference:
SH 62988 61307 (LIDAR)
Bwlch Height: 702.0m
(LIDAR)
Bwlch Grid Reference:
SH 62967 61278 (LIDAR)
Drop: 6.3m
(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 (July 2023)
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