The Beech (ST 346 974)
There has been a Summit Relocation to a hill that
is listed in the 100m Twmpau and Y Trechol – The Dominant Hills of Wales,
with the summit height, bwlch height and their locations, the drop and status
of the hill confirmed by LIDAR analysis conducted by Myrddyn Phillips.
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| LIDAR image of The Beech (ST 346 974) |
The criteria for the two listings that this summit
relocation applies to are:
100m Twmpau - Welsh hills at or above 100m and below 200m in height with 30m
minimum drop, with an accompanying sub list entitled the 100m Sub-Twmpau with the criteria for this sub category being all
Welsh hills at or above 100m and below 200m in height with 20m or more and
below 30m of drop, with the word Twmpau
being an acronym standing for thirty
welsh metre prominences and upward.
Y Trechol – The Dominant Hills of Wales – Welsh P30 hills whose
prominence equal or exceed half that of their absolute height. With the criteria for Lesser Dominant status being those additional Welsh P30 hills whose
prominence is between one third and half that of their absolute height. The list is authored by Myrddyn Phillips with
the Introduction to the start of the Mapping Mountains publication of this list
appearing on the 3rd December 2015.
The name the hill is now listed by is The Beech
and it is adjoined to the Cymoedd Gwent group of hills, which are situated in
the eastern part of South Wales (Region C, Sub-Region C2), and it has a
number of A roads encircling it with the A4042 to its west, the A472 to its
north, the A449 to its east and the M4 motorway towards its south, and has the
town of Brynbuga (Usk) towards its north-east.
When the original Welsh 100m P30 list was
published on Geoff Crowder’s v-g.me website this hill was listed with a 184m
summit height, based on the spot height positioned at ST 346 974 that appears
on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map, with the Ordnance
Survey Vector Map Local hosted on the Geograph website and which is entitled
the Interactive Coverage Map positioning this spot height on the south-east
side of a field boundary.
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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.
The summit height produced by LIDAR analysis is 185.4m
positioned at ST 34645 97459 with LIDAR also giving a 185.5m height positioned
at ST 34663 97467 to the raised field boundary that is excluded from the height
of this hill as it is considered a recent man-made construct. Importantly the natural summit position of
this hill is given by LIDAR to the north-west of the raised field boundary, and
as such comes
within the parameters of the Summit Relocations used within this page heading,
these parameters are:
The term Summit Relocations applies to any listed
hill whose summit meets the following criteria; where there are a number of
potential summit positions within close proximity and the highest point is not
where previously given, or a relocation of approximately 100 metres or more in
distance from either the position of a map spot height or from where the summit
of the hill was previously thought to exist, or when the summit of the hill is
in a different field compared to where previously given, or when the natural
and intact summit of a hill is confirmed compared to a higher point such as a
raised field boundary that is judged to be a relatively recent man-made
construct.
Therefore, the summit height produced by LIDAR
analysis is 185.4m to natural ground and this is positioned at ST 34645 97459, and
although relatively close to where 184m spot height appears on the Ordnance
Survey Vector Map Local hosted on the Geograph website, it is positioned in a
different field from where the originally listed summit adjoined to this spot
height is placed.
The full details for the hill are:
Group: Cymoedd Gwent
Name: The Beech
OS 1:50,000 map: 171
Summit Height: 185.4m (LIDAR,
natural summit)
Summit Grid Reference (new position): ST 34645 97459 (LIDAR, natural summit)
Bwlch Height: 89.0m (LIDAR)
Bwlch Grid Reference:
ST 34479 98091 (LIDAR)
Drop: 96.4m (LIDAR)
Dominance: 51.98%
(LIDAR)
Myrddyn Phillips (September 2019)
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