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

Crook (SD 664 935) – 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 by Joe Nuttall who produced a summit analysis programme using LIDAR, and then by LIDAR analysis conducted by Myrddyn Phillips. 

LIDAR image of Crook (SD 664 935)

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 listing of The Fours 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 2^nd edition of the booklet containing this list was published by Mapping Mountains Publications on the 24^th April 2018.

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

The name the hill is listed by is Crook, and it is adjoined to the The Calf group of hills, which are situated in the Howgill Fells (Region 35, Section 35A: The Northern Pennines), and it is positioned with the B6257 road to its west, the A684 road to its south and the A683 road to its east, and has the town of Sedbergh towards the south south-west.

When the 2^nd edition of the The Fours – The 400m Hills of England was published by Mapping Mountains Publications in April 2018, this hill was not included in the accompanying sub list, as it was considered not to meet the criteria used for this sub category. 

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

However, during the updating of this list for the 2^nd edition this hill was noted and listed with an estimated c 17m of drop, based on the 462m summit spot height that appears on the Harvey 1:25,000 Superwalker map to the Howgill Fells and an estimated c 445m col height based on interpolation of 10m contouring between 440m – 450m that appear on the Ordnance Survey 1:25,000 Explorer map. 

Extract from the Harvey 1:25,000 Superwalker map to the Howgill Fells

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 464.7m summit height and a 444.4m col height, with these values giving this hill 20.3m of drop, which is sufficient for it to be classified as a 400m Sub-Four.

 

The full details for the hill are:

Group:  The Calf

Name:  Crook

OS 1:50,000 map:  98

Summit Height:  464.7m (LIDAR)

Summit Grid Reference:  SD 66458 93550 (LIDAR)

Col Height:  444.4m (LIDAR)

Col Grid Reference:  SD 66410 93726 (LIDAR)

Drop:  20.3m (LIDAR)

 

Our thanks to Ronnie Bowron for bringing the details of this hill to our attention.

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 1^st 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 (August 2022)