Monday, 2 October 2023

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


High Moor (SJ 965 701) 

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 from LIDAR analysis conducted by Myrddyn Phillips. 

LIDAR image of High Moor (SJ 965 701)

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 list are three categories of sub hills; the 400m Sub-Four category, the 390m Sub-Four category and the 390m Double Sub-Four category.  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 Wales by Myrddyn Phillips and Aled Williams

The name the hill is listed by is High Moor, and it is adjoined to the Shining Tor group of hills, which are situated in the Peak District, and it is positioned encircled by minor roads with the A537 road farther to its north, the A523 road farther to its west and the A54 road farther to its south, and has the town of Macclesfield towards the north-west.

When the 1st edition of the The Fours was published by Europeaklist in December 2013, this hill was listed with a 415m summit height, based on the spot height that appeared on the Ordnance Survey Vector Map Local hosted on the Geograph website and which was entitled the Interactive Coverage Map and positioned at SJ 966 702. 

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

When the 2nd edition of the The Fours – The 400m Hills of England was published by Mapping Mountains Publications in April 2018 the details for this hill were examined by available LIDAR, resulting in a 415.8m summit height positioned at the same grid co-ordinates; SJ 966 702. 

LIDAR image showing the two tops of High Moor; the old summit position to the north-east and the new summit position to the south-west 

However, it was not until new LIDAR became available that the details for this hill could be again re-assessed.  The LIDAR (Light Detection & Ranging) technique produced highly accurate height data that is now freely available for much of England and Wales. 

Close up LIDAR image of the summit of High Moor (SJ 965 701)

The latest LIDAR analysis gives the highest ground on this hill as 416.1m positioned at SJ 96504 70128, 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 the latest LIDAR analysis is 416.1m and this is positioned at SJ 96504 70128.  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 135 metres south-westward from where the 415m spot height appeared on the Ordnance Survey Vector Map Local hosted on the Geograph website and which was entitled the Interactive Coverage Map, and also positioned in a different ring contour.

 

The full details for the hill are:

Group:  Shining Tor

Name:  High Moor

OS 1:50,000 map:  118

Summit Height:  416.1m (LIDAR)

Summit Grid Reference (New Position):  SJ 96504 70128 (LIDAR)

Col Height:  384.1m (LIDAR)

Col Grid Reference:  SJ 96803 70326 (LIDAR)

Drop:  32.0m (LIDAR)

 

Myrddyn Phillips and Aled Williams (October 2023)

 

 

  

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