Wednesday, 13 March 2024

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

 

Wittaburrow (SX 733 752) – 400m Sub-Four addition

There has been an addition 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 Wittaburrow (SX 733 752)

The criteria for the list that this addition 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 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 Wittaburrow and it is adjoined to the Broad Barrow group of hills, which are situated in Dartmoor, in the south-west of the country, and it is positioned with the B3387 road to its north and minor roads to its west, south and east, and has the town of Ashburton towards the south south-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 included as it was listed with 19m of drop, based on the 403m summit spot height that appears on the contemporary Ordnance Survey 1:25,000 Explorer map and the 384m col spot height that appeared on the Ordnance Survey Vector Map Local hosted on the Geograph website and which was entitled the Interactive Coverage Map. 

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

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 addition of this hill to 400m Sub-Four status is due to LIDAR analysis, resulting in a 404.1m summit height and a 383.5m col height, with these values giving this hill 20.6m of drop, which is sufficient for 400m Sub-Four status.

 

The full details for the hill are:

Group:  Broad Barrow

Name:  Wittaburrow

OS 1:50,000 map:  191

Summit Height:  404.1m (LIDAR)

Summit Grid Reference:  SX 73346 75210 (LIDAR)

Col Height:  383.5m (LIDAR)

Col Grid Reference:  SX 73397 75485 (LIDAR)

Drop:  20.6m (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 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 (March 2024)

 

  

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