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| LIDAR image of Chapman Barrows (SS 700 434) and 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.
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| The Fours - The 400m Hills of England by Myrddyn Phillips and Aled Williams |
The name the hill is listed by is Chapman Barrows, 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 a 458m col height, based on the 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.
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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 the summit of 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.
%20-%20LIDAR%20summit%201.jpg) |
| LIDAR summit image of Chapman Barrows (SS 700 434) |
The height produced by 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, 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 summit height produced by LIDAR analysis is 479.8m and this is positioned at SS 70003 43472. 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 north-westward from the high point of Wood Barrow.
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