Bryn Rhudd (SN 690 558 and SN 691 559)
There has been a Summit Relocation creating a twin summit to a hill that
is listed in the
Y Pedwarau – The 400m Hills of Wales,
with the summit height and its position confirmed
via LIDAR analysis conducted by Aled Williams.
 |
| LIDAR image of Bryn Rhudd (SN 690 558 and SN 691 559) |
The criteria for the list this
summit relocation affects are:
Y Pedwarau – The 400m Hills of Wales. Welsh hills at or above 400m and below 500m in height with 30m minimum drop, the list is co-authored by Myrddyn Phillips and Aled Williams and is published on Mapping Mountains in Google Doc format.
The name the hill is listed by is Bryn Rhudd and it is adjoined
to the Elenydd group of hills, which are situated in the northern part of Mid
and West Wales (Region B, Sub-Region B2), and is positioned with the B4343
road, the Afon Teifi and the A485 road to its north-west, and has the village of
Llanddewi Brefi towards the west.
When the original 400m height band of Welsh P30
hills were published on Geoff Crowder’s v-g.me website the summit height of
this hill was listed as 480m which was based on the spot height positioned at
SN 69179 55919 that appears on the Ordnance Survey 1:50,000 Landranger and
1:25,000 Explorer map.
 |
| Extract from the Ordnance Survey 1:25,000 Explorer map |
When the 1st edition of the Y Pedwarau was published by Europeaklist in May 2013 the hill
appeared under the details given above using the six figure grid reference of
SN 691 559. These details were amended
for the Y Pedwarau- The 400m Hills of
Wales list appearing on Mapping Mountains with the ten figure summit grid
reference of SN 69094 55832 used, with this being taken from hand-held GPS
submissions detailed on DoBIH.
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.
 |
| LIDAR summit image of Bryn Rhudd |
The summit height produced by LIDAR analysis is
479.6m at two points; SN 69091 55821 and SN 69199 55978 and this position in relation to that previously given 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 it is
positioned to a different feature such as in a conifer plantation, or when the
high point of the hill is placed within a different map contour compared to its
previous listed position, 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 479.6m and this is to two positions; SN
69091 55821 and SN 69199 55978, with the latter position to ground at the base
of a wall that bisects an ancient cairn and which is not given a spot height on
contemporary Ordnance Survey maps and is approximately 110 metres north
north-eastward from where the now twinned and previously listed summit is
positioned.
The full details for the hill are:
The full details for the hill are:
Group: Elenydd
Name: Bryn Rhudd
OS 1:50,000 map: 146
Summit Height: 479.6m
(LIDAR)
Summit Grid Reference (New Position): SN 69091 55821 and SN 69199 55978 (LIDAR)
Bwlch Height: c 443m (interpolation)
Bwlch Grid Reference:
SN 69888 56135 (interpolation)
Drop: c 37m (LIDAR
summit and interpolated bwlch)
Myrddyn Phillips and Aled Williams (February 2020)
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