Andrew’s Edge (SJ 984 747) – 400m Sub-Four deletion
There has been a deletion to the listing of 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 detail on contemporary maps produced from Ordnance Survey
data, and subsequently confirmed from LIDAR analysis conducted by Myrddyn Phillips.
%20-%20LIDAR%20hill%201.jpg) |
| LIDAR image of Andrew's Edge (SJ 984 747) |
This was initiated by Joe Nuttall who produced a summit analysis programme that used LIDAR with an alternative height map (DEM) allowing identification of summits and cols and thereby drops. The resulting spreadsheet that Joe produced contains over 29600 hills.
This spreadsheet is being evaluated by a number of
people, including Ronnie Bowron, who passed the details of this hill for
evaluation.
The criteria for the list that this deletion 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 deleted from 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 was listed by is Andrew’s Edge, and it is adjoined to the Shining Tor group
of hills, which are situated in the
Peak District in England, and it is
positioned with the A5004 road to its north-east, the B5470 road to its
north-west and the A537 road to its south, and has the towns of Macclesfield towards
the west and Buxton towards the east.
When the 2nd edition of the The Fours – The 400m Hills of England was published by Mapping Mountains Publications in April 2018, this hill was included
as a 400m Sub-Four and listed with 21m of drop, based on the 484m summit spot
height that appeared on the Ordnance Survey Vector Map Local hosted on the
Geograph website and which was entitled the Interactive Coverage Map, and the
463m col spot height that appears on the Harvey 1:40,000 British Mountain Maps
series to the Dark Peak.
 |
| Extract from the Ordnance Survey 1:25,000 Explorer map |
The details for this hill have now been
re-assessed against other digitally updated mapping. One of the mapping resources now available
online is the WalkLakes website which hosts an interactive Ordnance Survey map
originated from the Ordnance Survey Open Data programme. This map has many spot heights not on other
publicly available Ordnance Survey maps and for this hill a 485m spot height is
given on the area of its summit.
 |
| Extract from the WalkLakes website |
Another resource available online is the
interactive mapping originated from Ordnance Survey data hosted on the Magic
Maps website. This mapping also shows a 485m
spot height on the summit area of this hill.
 |
| Extract from the Magic Maps website |
The details for this hill were also re-assessed
against the mapping on the OS Maps website.
This is the replacement for OS Get-a-map and until recent times had
contours at 5m intervals which were proving consistently more accurate compared
to the 5m contours that sometimes appear on the Ordnance Survey 1:25,000
Explorer map and used to appear on the online Vector Map Local. This resulted in its col height being
estimated as c 466m based on interpolation of 5m contouring between 465m – 470m,
and this latter map and the interpolated col height is being favoured over the
spot height and its position given on the Harvey map.
 |
| Extract from the OS Maps website |
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.
Therefore, the deletion of this hill from 400m
Sub-Four status is due to re-assessment of contemporary mapping produced from
Ordnance Survey data, with subsequent confirmation from LIDAR analysis, resulting in a 484.8m summit height and a 465.0m
col height, with these values giving this hill 19.7m of drop,
which is insufficient for 400m Sub-Four status.
The full details for the hill are:
Group: Shining Tor
Name: Andrew’s Edge
OS 1:50,000 map: 118
Summit Height: 484.8m
(LIDAR)
Summit Grid Reference:
SJ 98438 74706 (LIDAR)
Col Height: 465.0m
(LIDAR)
Col Grid Reference: SJ
99028 74023 (LIDAR)
Drop: 19.7m (LIDAR)
For the additions, deletions and reclassifications to The Fours - The 400m Hills of England reported on Mapping Mountains
since the December 2013 publication of the list by Europeaklist please consult
the following Change Registers:
Our thanks to Ronnie Bowron for bringing the details of this
hill to our attention
Myrddyn Phillips and Aled Williams (November 2020)
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