Monday, 9 July 2018

Mapping Mountains – Hill Reclassifications – The Fours


Wansfell Pike (NY 394 041) – 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, coupled with information in the OS Trig Database and LIDAR analysis of the summit.  The Fours is the title for the list of 400m hills of England and takes in all English hills at or 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.

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 or 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 c 26m of drop with a summit height of c 483m based on an optical survey taken from the summit area of Baystones (486.9m at NY 40312 05143) which concluded that Wansfell Pike is at least 4m lower, and an estimated col height of c 457m based on col contouring between 450m – 460m on the 1:50,000 Landranger and 1:25,000 Explorer maps.

Extract from the Ordnance Survey 1:25,000 Explorer map

The name of the hill is Wansfell Pike and it is situated in the Eastern Fells of the Lake District and is placed in Region 34, Section 34C, with its Cardinal Hill being High Street (NY 440 110).  The hill is positioned between the A 591 road and the town of Ambleside which are to its west and the A 592 road which is to its east.

The summit of the hill is a part of designated open access land and can be approached from a number of directions with public footpaths leading to its summit from the west, north and east.

The reclassification of Wansfell Pike to Four status is due to the analysis of data on the OS Maps website, coupled with information in the OS Trig Database and LIDAR analysis of the summit.  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.  The OS Trig Database gives a buried block with a height of 483.717m at the summit of this hill and LIDAR analysis gives a summit height of 483.7m, and with an estimated col height of c 453 – c 454, based on col contours between 450m – 455m, these values are considered sufficient to list this hill with c 30m of drop. 
 
Extract from OS Maps

The full details for the hill are:

Cardinal Hill:  High Street

Summit Height:  483.7m (LIDAR)

Name:  Wansfell Pike

OS 1:50,000 map:  90

Summit Grid Reference:  NY 39417 04171 (LIDAR)

Drop:  c 30m


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 (July 2018)



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