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

 

Knott (NY 714 012) – Four reclassified to 400m Sub-Four

There has been a reclassification 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 prompted by Joe Nuttall who produced a summit analysis programme using LIDAR.  These details are being evaluated by a number of people, including Ronnie Bowron who passed the details of this hill to us.  LIDAR analysis was then conducted by Aled Williams and subsequently by Myrddyn Phillips. 

LIDAR image of Knott (NY 714 012)

The criteria for the list that this reclassification 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 reclassified 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 Knott, and it is adjoined to The Calf group of hills, which are situated in the Howgill Fells (Region 35, Section 35A: The Northern Pennines), and it is positioned with a minor road to its south-east, the A685 road to its north and the A683 road to its east, and has the village of Ravenstonedale towards the north north-east.

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

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 included as a Four and listed with an estimated c 31m of drop, based on the 1,522.8ft (464.2m) surface height on the Ordnance Survey series of Six-Inch maps and an estimated c 433m col height based on a comparison between Ordnance Survey 1:25,000 Explorer map and Harvey 1:25,000 Superwalker map col contours, with details in the accompanying Notes section stating; Four status assigned via comparison of OS and Harvey map col contours, with the former between 430m – 440m and the latter between 420m – 435m indicating that the col is between 430m – 435m, with an estimated height of c 433m and a drop of c 31m. 

Extract from the Ordnance Survey series of Six-Inch maps

Extract from the Harvey 1:25,000 Superwalker 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 reclassification of this hill to 400m Sub-Four status is due to LIDAR analysis, resulting in a 465.8m summit height and a 437.1m col height, with these values giving this hill 28.7m of drop, which is insufficient for it to be classified as a Four.

 

The full details for the hill are:

Group:  The Calf

Name:  Knott

OS 1:50,000 map:  91

Summit Height:  465.8m (LIDAR)

Summit Grid Reference:  NY 71422 01291 (LIDAR)

Col Height:  437.1m (LIDAR)

Col Grid Reference:  NY 70987 01254 (LIDAR)

Drop:  28.7m (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 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

 

Our thanks to Ronnie Bowron for passing on the details of this hill to us

Aled Williams and Myrddyn Phillips (March 2022)