Pt. 296.6m (SH 693 171) – 200m
Sub-Twmpau addition
There has been confirmation of an addition to the 200m Twmpau list due to LIDAR analysis conducted by Myrddyn Phillips, with the criteria for this list being:
200m Twmpau - Welsh hills at and above 200m and below 300m in height with 30m
minimum drop, with an accompanying sub list entitled the 200m Sub-Twmpau with the criteria for this sub category being all
Welsh hills at and above 200m and below 300m in height with 20m and more and
below 30m of drop, with the word Twmpau
being an acronym standing for thirty
welsh metre prominences and upward.
This hill was not listed in the Hills to be surveyed sub list when the
original Welsh P30 hills were published on Geoff Crowder’s v-g.me website as it
did not meet the criteria then used for this category of hill; however this
list has now been standardised and interpolated heights and drop values also
included, resulting in this hill being listed with 25m of drop, based on the
297m summit spot height and the 272m bwlch spot height that appear on the Ordnance
Survey Interactive Coverage Map hosted on the Geograph website.
Extract from the Ordnance Survey Interactive Coverage Map hosted on the Geograph website |
As the name of the ffridd
taking in this hill’s summit has not been confirmed the hill is being listed by
the point (Pt. 296.6m) notation and it is adjoined to the Cadair Idris group of hills, which are situated in the south-western
part of North Wales (Region A, Sub-Region A3), and the hill is positioned with
the A 493 road to its north and has the town of Dolgellau towards its east.
As the hill is a part of
designated open access land an ascent from most directions is feasible, with a
minor road towards its east and a public footpath towards its north and a
bridleway towards its south probably giving the easiest option for ascent.
The confirmation of the addition
of this hill to 200m Sub-Twmpau
status is due to LIDAR analysis conducted by Myrddyn Phillips. The LIDAR (Light Detection & Ranging)
technique produced highly accurate height data that is now freely available for
much of England and Wales.
The 1m DTM LIDAR analysis gives the hill the
following details:
Name: Pt. 296.6m
Summit Height: 296.6m
Summit Grid Reference:
SH 69333 17107
Bwlch Height: 272.2m
Bwlch Grid Reference:
SH 69427 17196
Drop: 24.4m
Therefore, the 296.6m LIDAR analysis for the
summit position at SH 69333 17107 and the 272.2m LIDAR analysis for
the bwlch position at SH 69427 17196 gives this hill 24.4m of drop, which
confirms its addition to 200m Sub-Twmpau
status.
The full details for the hill are:
Group: Cadair Idris
Name: Pt. 296.6m
OS 1:50,000 map: 124
Summit Height: 296.6m
(LIDAR)
Summit Grid
Reference: SH 69333 17107 (LIDAR)
Bwlch
Height: 272.2m (LIDAR)
Bwlch Grid
Reference: SH 69427 17196 (LIDAR)
Drop: 24.4m (LIDAR)
Myrddyn Phillips (May 2018)
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