Pt. 465.1m (NT 830 141) – 400m Sub-Four reclassified to Four
There has been a reclassification to the listing of The Fours due to analysis of data on the
OS Maps website, which is the recent replacement for OS Get-a-map with confirmation from subsequent LIDAR analysis conducted by Myrddyn Phillips. The
Fours is the title for the list of 400m hills of England and takes in all
English hills at and above 400m and below 500m in height that have a minimum
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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| Pt. 465.1m (NT 830 141). Photo: Rob Woodall |
Accompanying the main list of The Fours are three categories of sub hills, with this hill being
reclassified from the 400m Sub-Fours. The criteria for 400m Sub-Four status are all English hills at and above 400m and
below 500m in height that have 20m or more and below 30m of drop.
Prior to analysis of data on OS Maps this hill was listed
with an estimated c 28m of drop, based on the 465m summit spot height that appears on the
Ordnance Survey 1:25,000 Explorer map and an estimated c 437m col height, based on interpolation of 10m contouring between 430m – 440m that appear on the 1:50,000 Landranger and
1:25,000 Explorer map.
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| Extract from the Ordnance Survey Interactive Coverage Map hosted on the Geograph website |
As the authors do not know an individual name for this hill
it appears listed under the point (Pt. 465.1m) notation and it is situated in the
Scottish Border to the River Tyne area and is placed in Region 33, with its
Cardinal Hill being The Cheviot (NT 909 205).
The hill is positioned between the Westhope Burn to its west and the Easthope
Burn to its east and is within 600 metres of the border with Scotland which is
to its north north-west.
The summit of the hill is a part of designated open access
land and can be approached from the Pennine Way that follows the course of the
border hereabouts or from the stream valley to its south, with other options
for access following hill ridges either side of the ridge this hill is situated
on.
 |
| The summit of Pt. 465.1m (NT 830 141). Photo: Rob Woodall |
The initial reclassification of this hill from Sub-Four status is due to analysis of data
on the OS Maps website. This mapping
gives contour intervals at 5m which has enabled the height of the col to be
narrowed down compared to the 10m contour intervals given on the Ordnance
Survey 1:50,000 Landranger and 1:25,000 Explorer map. Therefore with a 465m summit spot height on
the 1:25,000 Explorer map and an estimated col height of c 433m, based on col
contouring on OS Maps between 430m – 435m, this hill is now listed with an estimated c 32m
of drop, which is sufficient for it to be reclassified to Four status.
 |
| Extract from OS Maps |
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.
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LIDAR image of Pt. 465.1m (NT 830 141)
Therefore, the confirmation of the reclassification of this hill from Sub-Four status is due to LIDAR analysis, resulting in a 465.1m summit
height and a 433.1m col height, with these values giving this hill 32.1m of
drop, which is sufficient for it to be classified as a Four.
The full details for the hill are:
Cardinal Hill: The
Cheviot
Name: Pt. 465.1m
OS 1:50,000 map: 80
Summit Height: 465.1m (LIDAR)
Summit Grid Reference:
NT 83019 14191 (LIDAR)
Col Height: 433.1m (LIDAR)
Col Grid Reference: NT 82972 14294 (LIDAR)
Drop: 32.1m (LIDAR)
For the additions, deletions and reclassifications to The Fours reported on Mapping Mountains
since the December 2013 publication of the list by Europeaklist please consult
the following Change Registers:
Myrddyn Phillips and Aled Williams (June 2018)
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