Thursday 11 October 2018

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


Anthony Hill (SK 046 706) – 400m Sub-Four addition

There has been an addition to the listing of The Fours - The 400m Hills of England, with the summit height, col height and their locations, the drop and status of the hill derived from detail on contemporary maps produced from Ordnance Survey data and subsequently confirmed by LIDAR analysis conducted by Myrddyn Phillips.

LIDAR image of Anthony Hill (SK 046 706)

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

The Fours – The 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 added to 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 Fours - The 400m Hills of England by Myrddyn Phillips and Aled Williams

The name the hill is listed by is Anthony Hill, and it is adjoined to the Axe Edge group of hills, which are situated in the Peak District, and it is positioned with a minor road to its north and south, and the A53 road to its west, and has the town of Buxton to the north north-east.

When the 1st edition of the The Fours was published by Europeaklist in December 2013, this hill was not included in the 400m Sub-Four caregory, but was listed with an estimated c 18m of drop, based on the 414m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and an estimated c 396m col height based on 5m contouring between 395m – 400m that also appear on the Ordnance Survey 1:25,000 Explorer map.

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

One of the resources recently available online is the mapping on the OS Maps website and the details for this hill were subsequently re-assessed against this mapping.  This is the replacement for OS Get-a-map and until recent times had contours at 5m intervals which were proving consistently more accurate compared to the 5m contours that sometimes appear on the Ordnance Survey 1:25,000 Explorer map and used to appear on the online Vector Map Local.  This mapping had col contouring between 385m – 390m, with interpolation placing the height of the col as an estimated c 389m.


Extract from 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 confirmation of the addition of this hill to 400m Sub-Four status is due to LIDAR analysis, resulting in a 413.3m summit height and a 385.9m col height, with these values giving this hill 27.4m of drop, which is sufficient for it to be classified as a 400m Sub-Four. 


The full details for the hill are:

Group:  Axe Edge

Name:  Anthony Hill

OS 1:50,000 map:  119

Summit Height:  413.3m (LIDAR)

Summit Grid Reference:  SK 04646 70659 (LIDAR)

Col Height:  385.9m (LIDAR)

Col Grid Reference:  SK 04492 70608 (LIDAR)

Drop:  27.4m (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 (October 2018)







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