Tuesday, 18 October 2022

Mapping Mountains – Summit Relocations – The Fours – The 400m Hills of England


Pt. 414.7m (SK 109 679) 

There has been a Summit Relocation to a hill that is listed in 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 initially conducted by Jim Bloomer and subsequently by Myrddyn Phillips. 

LIDAR image of Pt. 414.7m (SK 109 679) and Nether Low (SK 110 688)

The criteria for the list that this summit relocation 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 listing of The Fours are three categories of sub hills, with this hill 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 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 hill is being listed by the point (Pt. 414.7m) notation as an appropriate name for it either through local enquiry and/or historic research has not been found by the authors, and it is adjoined to the Axe Edge group of hills, which are situated in The Southern Pennines (Region 36), and it is positioned with the A515 road to its south and a minor road to its east, and has the town of Buxton towards the north-west.

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 listed with a summit height of 414m based on the spot height that appears on the Ordnance Survey 1:25,000 Explorer map and which is positioned at SK 11076 68874, with an accompanying note stating; A potential higher summit has been reported by a number of people, including Adrian Rayner and Carole Engel and is positioned at SK 10994 67973.

 

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. 

LIDAR summit image of Pt. 414.7m (SK 109 679)

LIDAR analysis gives the highest ground on this hill as 414.7m positioned at SK 10999 67962 and this comes within the parameters of the Summit Relocations used within this page heading, these parameters are:

The term Summit Relocations applies to when the high point is positioned in a different field, to a different feature such as a conifer plantation, within a different map contour, a different point where a number of potential summit positions are within close proximity, when natural ground or the natural and intact summit is confirmed compared to a higher point such as a raised field boundary or covered reservoir that is considered a relatively recent man-made construct, or a relocation of approximately 100 metres or more in distance from either the position of a map spot height or from where the summit of the hill was previously thought to exist.

Therefore, the summit height produced by LIDAR analysis is 414.7m and this is positioned at SK 10999 67962.  This position is not given a spot height on the contemporary Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map, and is approximately 900 metres southward from where the previously listed summit is positioned. 

 

The full details for the hill are:

Group:  Axe Edge

Name:  Pt. 414.7m

OS 1:50,000 map:  119

Summit Height:  414.7m (LIDAR)

Summit Grid Reference (New Position):  SK 10999 67962 (LIDAR)

Col Height:  385.5m (LIDAR)

Col Grid Reference:  SK 10588 67661 (LIDAR)

Drop:  29.2m (LIDAR)

 

Myrddyn Phillips and Aled Williams (October 2022)

 

  

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