Pt. 571.3m (SH 661 498) – Welsh Highland
Sub addition
There has been an addition 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 for the Welsh Highlands – Uchafion Cymru list authored by
Aled Williams and Myrddyn Phillips.
|
LIDAR image of Pt. 571.3m (SH 661 498) |
The criteria for the list that this addition applies to are:
|
Welsh Highlands - Uchafion Cymru by Myrddyn Phillips and Aled Williams |
The hill is being listed by the point (Pt. 571.3m)
notation and it is adjoined to the Moelwyn Mawr group of hills, which are situated in the north-western part of
North Wales (Region A, Sub-Region A2), and
it is positioned with the A498 road to its north-west, a minor road to its
west, and the A470 road to its east, and has the town of Blaenau Ffestiniog
towards the south-east.
This hill was not included in the initial P10 sub
list when it was completed in June 2020 as with an estimated c 572m summit height
and an estimated c 564m bwlch height, with both heights on interpolation of 10m
contouring, these values gave this hill an estimated c 8m of drop.
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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 addition of this hill to Welsh
Highland Sub status is due to LIDAR analysis, resulting in a 571.3m summit
height and a 560.9m bwlch height, with these values giving this hill 10.4m of
drop, which is sufficient for it to be classified as a Welsh Highland Sub.
The full details for the hill are:
Group: Moelwyn Mawr
Name: Pt. 571.3m
OS 1:50,000 map: 115
Summit Height: 571.3m
(LIDAR)
Summit Grid Reference:
SH 66153 49880 (LIDAR)
Bwlch Height: 560.9m
(LIDAR)
Bwlch Grid Reference:
SH 66223 49897 (LIDAR)
Drop: 10.4m
(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 (May 2023)
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