Brynele (SN 570 609) – Sub-Trichant addition
There has been confirmation of an addition to the list of Y Trichant – The 300m Hills of Wales, with the summit height, bwlch height and their locations, the drop and status of the hill derived from LIDAR analysis conducted by Myrddyn Phillips.
LIDAR image of Brynele (SN 570 609) |
The criteria for the list that this addition
applies to are:
Y Trichant
– The 300m Hills of Wales – Welsh
hills at or above 300m and below 400m in height that have 30m minimum drop, with an accompanying sub list entitled the
Sub-Trichant, with the criteria for this sub category being all Welsh hills at
or above 300m and below 400m in height with 20m or more and below 30m of
drop. The list is authored by Myrddyn Phillips with the
Introduction to the list and the renaming of it appearing on Mapping Mountains
on the 13th May 2017, and the Introduction to the Mapping Mountains
publication of the list appearing on the 1st January 2022.
Y Trichant - The 300m Hills of Wales by Myrddyn Phillips |
The name the hill is listed by is Brynele and this
was derived from the Tithe map, and it is adjoined to the Mynydd Bach group of
hills, which are situated in the western
part of South Wales (Region B, Sub-Region B1), and it is positioned with minor roads to its north,
west and south, with the B4576 road to its east, and has the village of
Llangeitho towards the east south-east.
When the original 300m height band of Welsh P30 hills were published on Geoff Crowder’s v-g.me website, this hill was not
included in the Hills to be surveyed
sub list, as it was considered not to meet the criteria then used for this sub
category.
When the sub list was standardised, and
interpolated heights and drop values also included the details for this hill
were re-evaluated and it was listed with 21m of drop, based on the 304m summit
spot height that appears on the contemporary Ordnance Survey 1:50,000
Landranger and 1:25,000 Explorer map, and the 283m bwlch spot height that
appeared on the Ordnance Survey Vector Map Local hosted on the Geograph website
and which was entitled the Interactive Coverage 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 confirmation of the addition of
this hill to Sub-Trichant status is due to LIDAR analysis, resulting in a
303.4m summit height and a 283.3m bwlch height, with these values giving this
hill 20.1m of drop, which is sufficient for it to be classified as a
Sub-Trichant.
The full details for the hill are:
Group: Mynydd Bach
Name: Brynele
OS 1:50,000 map: 146
Summit Height: 303.4m (LIDAR)
Summit Grid Reference: SN 57034 60907 (LIDAR)
Bwlch Height: 283.3m (LIDAR)
Bwlch Grid Reference: SN 56637 60817 (LIDAR)
Drop: 20.1m (LIDAR)
Myrddyn Phillips
(December 2023)
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