Thursday, 25 September 2025

Mapping Mountains – Significant Height Revisions – The Fours – The 400m Hills of England


Galloway Pasture (SE 109 632) 

There has been a Significant Height Revision 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 Galloway Pasture (SE 109 632)

The criteria for the list that this height revision 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 is a sub list entitled the Sub-Fours, the criteria for which are all English hills at or above 400m and below 500m in height that have 15m or more and below 30m of drop.  The list is co-authored by Myrddyn Phillips and Aled Williams and is available to download in Google Doc format from the Mapping Mountains site.

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

The name the hill is listed by is Galloway Pasture, and it is adjoined to the Whernside group of hills, which are situated in the Pennines of northern England, and it is positioned with the B6265 road to its north and a minor road to its east, and has the town of Pateley Bridge towards the east north-east.

When the Introduction to the first group of hills for the updated and revised listing of the The Fours – The 400m Hills of England was published by Mapping Mountains on the 10th September 2022, it was announced that the accompanying sub lists were being revised with the two 390m categories dispensed with and the criteria and name of the 400m Sub-Fours revised.  The one accompanying sub list is now named the Sub-Fours with its criteria being all English hills 400m and above and below 500m in height that have 15m and more and below 30m of drop.

Prior to this revision this hill was listed with an estimated c 19m of drop, based on the 425m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and an estimated c 406m col height, based on interpolation of 10m contouring between 400m – 410m. 

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 Galloway Pasture (SE 109 632)

LIDAR analysis gives the height of this hill as 427.5m and when compared to its originally listed summit height this comes within the parameters of the Significant Height Revisions used within this page heading, these parameters are:

The term Significant Height Revisions applies to any listed hill whose interpolated height and Ordnance Survey, Harvey or other interactive map summit spot height has a 2m or more discrepancy when compared to the survey result produced by the Trimble GeoXH 6000 or analysis of data produced via LIDAR.  Also included are hills whose summit map data is missing an uppermost ring contour when compared with the data produced by the Trimble or by LIDAR analysis.

Therefore, the new listed summit height of this hill is 427.5m and this was derived from LIDAR analysis, this is 2.5m higher than the originally listed summit height, which was based on 425m spot height that appears on the Ordnance Survey 1:25,000 Explorer map. 

 

The full details for the hill are:

Group:  Whernside

Name:  Galloway Pasture

OS 1:50,000 map:  99

Summit Height (New Height):  427.5m (LIDAR)

Summit Grid Reference:  SE 10920 63236 (LIDAR)

Col Height:  409.7m (LIDAR)

Col Grid Reference:  SE 10918 63764 (LIDAR)

Drop:  17.9m (LIDAR)

 

Myrddyn Phillips and Aled Williams (September 2025)

 

 

  

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