Pt. 426.8m (NY 272 143) – Sub-Four addition
There has been an addition 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 LIDAR analysis conducted by Myrddyn Phillips.
|
LIDAR image of Pt. 426.8m (NY 272 143) |
The criteria for the list that this addition
applies to are:
|
The Fours - The 400m Hills of England by Myrddyn Phillips and Aled Williams |
The hill is listed by the point (Pt. 426.8m) notation, and it is adjoined to the High Raise
group of hills, which are
situated in the English Lake District, and it is positioned with the B5289 road
to its west, and has the small community of Rosthwaite towards the west north-west.
When the Introduction to the first group of hills for
the updated and revised listing of the The
Fours – The 400m Hills of England was published by Mapping Mountains on the
10th September 2022, it was announced that the accompanying sub
lists were being revised with the two 390m categories dispensed with and the
criteria and name of the 400m Sub-Fours revised. The one accompanying sub list is now named
the Sub-Fours with its criteria being all English hills 400m and above and
below 500m in height that have 15m and more and below 30m of drop.
Prior to this revision this hill was not listed,
with subsequent interpolation giving it an estimated c 10m of drop, based on an
estimated c 427m summit height and an estimated c 417m col height, with both
heights based on interpolation of 10m contouring that appears on the Ordnance
Survey 1:25,000 Explorer map.
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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 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 addition of this hill to Sub-Four
status is due to LIDAR analysis, resulting in a 426.8m summit height and a 411.1m
col height, with these values giving this hill 15.7m of drop, which is
sufficient for it to be classified as a Sub-Four.
The full details for the hill are:
Group: High Raise
Name: Pt. 426.8m
OS 1:50,000 map: 89,
90
Summit Height: 426.8m
(LIDAR)
Summit Grid Reference:
NY 27236 14340 (LIDAR)
Col Height: 411.1m
(LIDAR)
Col Grid Reference: NY
27236 14507 (LIDAR)
Drop: 15.7m (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 1st
edition of this list by Europeaklist please consult the following Change
Registers:
The Fours
Sub-Fours
Myrddyn Phillips and Aled Williams (January 2025)
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