Wood Barrow (SS 716 425)
There has been a Summit Relocation to a hill that is listed in the The Fours – The 400m Hills of England, with the summit height, col height and their locations, the drop and status of the hill derived from LIDAR analysis conducted by Myrddyn Phillips.
LIDAR image of Wood Barrow (SS 716 425) |
The criteria for the list that this summit
relocation applies to are:
The Fours – The 400m Hills of England.
English hills at or above 400m and below 500m in height that have 30m
minimum drop, accompanying the main list are three categories of sub hills,
with this hill being included in the 400m Sub-Four category, the criteria for
which are all English hills at or above 400m and below 500m in height that have
20m or more and below 30m of drop. The
list is co-authored by Myrddyn Phillips and Aled Williams and the 2nd
edition of the booklet containing this list was published by Mapping Mountains
Publications on the 24th April 2018.
The Fours - The 400m Hills of England by Myrddyn Phillips and Aled Williams |
The name the hill is listed by is Wood Barrow, and
it is adjoined to the Dunkery Beacon group of hills, which are
situated in the counties of Somerset and Devon, and it is positioned with the A39 road to its
north-west and the B3358 road to its south, and has the small community of
Parracombe towards the west north-west.
When the 1st edition of the The Fours was published by Europeaklist in
December 2013, the qualifying 400m Sub-Four hill was listed as Wood Barrow (SS
716 425) with 22m of drop, based on the 480m summit spot height that appears on
the contemporary Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map
and the 458m col spot height that appears on the contemporary Ordnance Survey
1:25,000 Explorer map, with an accompanying note stating:
Although
Chapman Barrows at SS 700 434 has a 480m map height, it is not listed as a twin
Sub-Four as its 480.093m flush bracket height means ground at the base of the
trig pillar will be below 480m.
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.
LIDAR image of Chapman Barrows (SS 700 434) and Wood Barrow (SS 716 425) |
The height produced by initial LIDAR analysis to
the high point of Chapman Barrows is 479.8m positioned at SS 70003 43472 and to
the high point of Wood Barrow is 479.7m positioned at SS 71627 42506, resulting
in the summit of the qualifying 400m Sub-Four being relocated from Wood Barrow
to Chapman Barrows.
LIDAR summit image of Wood Barrow (SS 716 425) |
However, the latest available LIDAR analysis gives
the high point of Chapman Barrows as 479.8m positioned at SS 70003 43471 and
the high point of Wood Barrow as 480.0m positioned at SS 71627 42505, and this
comes within
the parameters of the Summit Relocations used within this page heading, these
parameters are:
The term Summit Relocations applies to when the
high point is positioned in a different field, to a different feature such as a
conifer plantation, within a different map contour, a different point where a
number of potential summit positions are within close proximity, when natural
ground or the natural and intact summit is confirmed compared to a higher point
such as a raised field boundary or covered reservoir that is considered a
relatively recent man-made construct, 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.
Therefore, the height
produced by the latest available LIDAR analysis to the summit of Wood Barrow is
480.0m and this is positioned at SS
71627 42505. This position is adjacent to where the 480m
spot height appears on the contemporary Ordnance Survey 1:50,000 Landranger and
1:25,000 Explorer map and is approximately 1.8km south-eastward from the summit
of Chapman Barrows which LIDAR gives as 0.2m lower.
The full details for the hill are:
Group: Dunkery Beacon
Name: Wood Barrow
OS 1:50,000 map: 180
Summit Height: 480.0m
(LIDAR)
Summit Grid Reference (New Position): SS 71627 42505 (LIDAR)
Col Height: 457.7m (LIDAR)
Col Grid Reference: SS
72621 42582 (LIDAR)
Drop: 22.3m (LIDAR)
Myrddyn Phillips and Aled Williams (January 2024)
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