Wednesday 4 July 2018

Mapping Mountains – Hill Reclassifications – The Fours - The 400m Hills of England


Little Meldrum (NY 422 227) – 400m Sub-Four deletion

There has been a deletion from 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.  With the summit height, col height and their locations, the drop and status of the hill subsequently confirmed by LIDAR analysis conducted by Myrddyn Phillips.

LIDAR image of Little Meldrum (NY 422 227)

The criteria for the list that this deletion applies to are:

The FoursThe 400m Hills of England.  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-Four category, 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.

The name the hill is listed by is Little Meldrum 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 Helvellyn (NY 342 151).  The hill is positioned above Ullswater which is to its south-east and is situated between the small communities of Matterdale End to the west north-west and Pooley Bridge to the east north-east.

As the summit of the hill is not a part of designated open access land permission to visit should be sought, for those wishing to do so it can be approached via a public footpath that skirts the summit of the hill to its south, or it can be combined with near neighbours to take in a linear ridge walk.

Prior to analysis of data on the OS Maps website this hill was listed with an estimated c 20m of drop, based on the 404m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and an estimated c 384m col height based on interpolation of 10m contouring between 380m – 390m.


Extract from the Ordnance Survey Interactive Coverage Map hosted on the Geograph website

The deletion of Little Meldrum from 400m Sub-Four status is due to the analysis of data on the OS Maps website.  This mapping has 5m contour intervals which enables the height of the col to be narrowed down when compared to the 10m contour intervals on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer maps.  

Therefore, with a 404m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and an estimated c 388m col height, based on interpolation of OS Maps contouring between 385m – 390m, this hill is listed with an estimated c 16m of drop, which is insufficient for its continued inclusion as a 400m Sub-Four.

Extract from OS Maps

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 confirmation of the deletion of this hill from 400m Sub-Four status is due to LIDAR analysis, resulting in a 403.6m summit height and a 385.1m col height, with these values giving this hill 18.6m of drop, which is insufficient for it to be classified as a 400m Sub-Four.



The full details for the hill are:

Cardinal Hill:  Helvellyn

Name:  Little Meldrum

OS 1:50,000 map:  90

Summit Height:  403.6m (LIDAR)

Summit Grid Reference:  NY 42201 22772 (LIDAR)

Col Height:  385.1m (LIDAR)

Col Grid Reference:  NY 42313 22850 (LIDAR)

Drop:  18.6m (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 list by Europeaklist please consult the following Change Registers:










Myrddyn Phillips and Aled Williams (July 2018)



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