Pt. 476.0m (NY 399 044) – 400m 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 prompted by Joe Nuttall who produced a summit analysis programme using
LIDAR, and then confirmed by LIDAR analysis conducted by Myrddyn Phillips, with the col having been surveyed with a Leica GS15 by John Barnard, Jim Bloomer and Graham Jackson.
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LIDAR image of Pt. 476.0m (NY 399 044) |
The criteria for the list that this addition
applies to are:
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The Fours - The 400m Hills of England by Myrddyn Phillips and Aled Williams |
The hill is being listed by the point (Pt. 476.0m) notation
as an appropriate name for it either through local enquiry and/or historic
research has not been found by the authors, and it is adjoined to the High Street group of hills, which are situated in The
Lake District (Region 34, Section 34C: The Eastern Fells), and it is positioned
with a minor road to its north-west, the A591 road to its west and the A592
road to its east, and has the town of Ambleside towards the west.
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
not included in the accompanying sub list, as it was considered not to meet the
criteria used for this sub category.
However, during the updating of this list for the
2nd edition this hill was noted and listed with an estimated c 17m
of drop, based on the 474m 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 an estimated c 457m col height, based on
interpolation of 10m contouring between 450m – 460m.
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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 400m
Sub-Four status is due to LIDAR analysis and the height and position of the col confirmed by a Leica GS15 survey, resulting in a 476.0m summit height
and a 454.8m col height, with these values giving this hill 21.2m of drop,
which is sufficient for it to be classified as a 400m Sub-Four.
The full details for the hill are:
Group: High Street
Name: Pt. 476.0m
OS 1:50,000 map: 90
Summit Height: 476.0m
(LIDAR)
Summit Grid Reference:
NY 39930 04485 (LIDAR)
Col Height: 454.8m
(Leica GS15)
Col Grid Reference: NY
39696 04372 (Leica GS15)
Drop: 21.2m (LIDAR summit and Leica GS15 col)
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
The Fours – 400m Sub-Four
The Fours – 390m Sub-Four
The Fours – 390m Double Sub-Four
Myrddyn Phillips and Aled Williams (October 2022)
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