Monday, 21 May 2018

Mapping Mountains – Hill Reclassifications – The Fours

Pt. 430.7m (NY 308 042) – 400m Sub-Four deletion

There has been a deletion from the listing of The Fours due to LIDAR analysis conducted by Aled Williams.  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.

Accompanying the main list of The Fours are three categories of sub hills, with this hill being deleted 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 and more and below 30m of drop.  

Prior to LIDAR analysis this hill was listed with c 20m of drop based on an estimated summit height of c 431m (hence its previously listed name of Pt. c 431m) based on a small uppermost 430m ring contour that appears on the Ordnance Survey 1:25,000 Explorer map and a 411m col height that appears on 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. 430.7m) notation and it is situated in the Central and Western Fells of the Lake District and is placed in Region 34, Section 34B, with its Cardinal Hill being Scafell Pike (NY 215 072).  The hill is positioned between Great Langdale to its north and Little Langdale to its south and has the village of Elterwater towards its east north-east.

As the summit of the hill is a part of designated open access land it can be approached from a number of directions, with access from the north-west and from the east probably being the most convenient.

The deletion of Pt. 430.7m from 400m Sub-Four status is due to LIDAR analysis conducted by Aled Williams.  The LIDAR (Light Detection & Ranging) technique produced highly accurate height data that is now freely available for much of England and Wales.

Aled’s LIDAR analysis gives the hill the following details:

Pt. 430.7m

Summit Height:  430.7m

Summit Grid Reference:  NY 30845 04225

Col Height:  412.6m

Col Grid Reference:  NY 30755 04313

Drop:  18.1m

Therefore, the 430.7m LIDAR analysis for the summit position at NY 30845 04225 and the 412.6m LIDAR analysis for the col position at NY 30755 04313 gives this hill 18.1m of drop, which is insufficient for it to retain its 400m Sub-Four status.

The full details for the hill are:

Cardinal Hill:  Scafell Pike

Summit Height:  430.7m (LIDAR)

Name:  Pt. 430.7m

OS 1:50,000 map:  90

Summit Grid Reference:  NY 30845 04225 (LIDAR)

Drop:  18.1m (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 (May 2018)

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