Brownberry (NY 940 208) – 400m Sub-Four deletion
There has been a deletion to the listing of The Fours - The 400m Hills of England due to analysis of data on the OS Maps website, which is the recent replacement for OS Get-a-map and confirmed by subsequent LIDAR analysis conducted by Myrddyn Phillips.
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| LIDAR image of Brownberry (NY 940 208) |
The criteria for the list that this deletion applies to are:
The Fours - The 400m Hills of England takes in all 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-Fours; 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 Brownberry and it is situated in the Northern and Central Pennines and is placed in Region 35, Section 35A with its Cardinal Hill being Cross Fell (NY 687 343). The hill is positioned above the Grassholme Reservoir which is to its north and the Hury Reservoir to its south-east and has the small market town of Middleton-in-Teesdale towards the north.
Prior to analysis of data on OS Maps this hill was listed
with an estimated c 20m of drop, based on the 406m summit spot height that appears on the
Ordnance Survey 1:50,000 Landranger map and an estimated c 386m col height based on interpolation of 10m contouring between 380m – 390m that appear on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer maps.
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| Extract from the Ordnance Survey 1:50,000 Landranger map |
The deletion of this hill from 400m Sub-Four status is due to the
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 when compared to the 10m contour intervals given
on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer maps.
Therefore, with a 406m summit spot height on the Ordnance Survey 1:50,000 Landranger map and an estimated c 388m col height, based on interpolation of contouring between 385m – 390m, this hill is now listed with an estimated c 18m of drop, which is insufficient for its continued inclusion as a 400m Sub-Four.
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| Extract from the interactive mapping hosted on 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 analysis of data on the OS Maps website, which is the recent replacement for OS Get-a-map and confirmed by subsequent LIDAR analysis, resulting in a 406.7m summit height and a 388.0m col height, with these values giving this hill 18.7m of drop, which is insufficient for it to be classified as a 400m Sub-Four.
The full details for the hill are:
Cardinal Hill: Cross Fell
Name: Brownberry
OS 1:50,000 map: 91, 92
Summit Height: 406.7m (LIDAR)
Summit Grid Reference: NY 94069 20879 (LIDAR)
Col Height: 388.0m (LIDAR)
Col Grid Reference: NY 94979 21421 (LIDAR)
Drop: 18.7m (LIDAR)
For the additions, deletions and reclassifications to The Fours reported on Mapping Mountains
since the December 2013 publication of the 1st edition of this list
by Europeaklist please consult the following Change Registers:
Myrddyn Phillips and Aled Williams (July 2018)
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