Tuesday, 31 January 2023

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


Burners Hills (NY 942 172) – 400m Sub-Four deletion

There has been a deletion to the listing of the 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 LIDAR analysis conducted by Myrddyn Phillips. 

LIDAR image of Burners Hills (NY 942 172)

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

The name the hill is listed by is Burners Hills and it is adjoined to the Cross Fell group of hills, which are situated in the northern Pennines, and it is positioned with the B6276 road to its north-west, the A66 road to its south and the B6277 road to its east, and has the town of Barnard Castle towards the east.

When the 2nd edition of the The Fours – The 400m Hills of England was published by Mapping Mountains Publications in April 2018, this hill was not classified but was listed with an estimated c 17m of drop, based on the 404m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and an estimated c 387 col height based on interpolation of 5m contouring between 385m – 390m that appeared on the OS Maps website. 

Extract from the Ordnance Survey 1:25000 Explorer map

The mapping on the OS Maps website is the replacement for OS Get-a-map and had contours at 5m intervals which were consistently more accurate compared to the 5m contours that sometimes appear on Ordnance Survey 1:25,000 Explorer maps and used to appear on the online Vector Map Local.  This mapping is digitally updated and had altered since the details for this hill were re-evaluated for the 2nd edition of the booklet published in April 2018, as the col contouring was now between 380m – 385m.  This is not a one off, as a number of examples have been noted where the contours on this mapping have subsequently changed since first being evaluated.  This re-assessment resulted in an estimated c 383m col height and when coupled with the 404m summit spot height, these values gave this hill an estimated c 21m of drop and it was subsequently listed as a 400m Sub-Four. 

Extract from the interactive mapping that used to be 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 LIDAR analysis, resulting in a 403.1m summit height and a 383.2m col height, with these values giving this hill 19.9m of drop, which is insufficient for it to be classified as a 400m Sub-Four.

 

The full details for the hill are:

Group:  Cross Fell

Name:  Burners Hills

OS 1:50,000 map:  91, 92

Summit Height:  403.1m (LIDAR)

Summit Grid Reference:  NY 94228 17203 (LIDAR)

Col Height:  383.2m (LIDAR)

Col Grid Reference:  NY 94255 16900 (LIDAR)

Drop:  19.9m (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 1st edition of this list by Europeaklist please consult the following Change Registers:

 

The Fours

 

The Fours – 400m Sub-Four

 

The Fours – 390m Sub-Four

 

The Fours – 390m Double Sub-Four

 

Myrddyn Phillips and Aled Williams (January 2023) 

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