Tuesday, 29 November 2022

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


Cold Stones (SE 125 636) 

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 prompted by Joe Nuttall who produced a summit analysis programme using LIDAR, and then confirmed by LIDAR analysis conducted by Myrddyn Phillips. 

LIDAR image of Cold Stones (SE 125 636)

The criteria for the list this height revision affects 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, with this hill reclassified from 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 name the hill is listed by is Cold Stones, and it is adjoined to the Whernside group of hills, which are situated in the Yorkshire Dales, and it is positioned with the B6265 road to its north and a minor road to its west, and has the town of Pateley Bridge towards the east north-east.

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 included as a 400m Sub-Four and listed with an estimated c 26m of drop, based on an estimated c 417m summit height positioned at SE 120 641 and a 391m col height, the latter 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, with an accompanying note stating; The one that got away, or more appropriately, the one that was quarried away, as Cold Stones was once an English 400m P30, with an imperial height of 1,403ft (427.6m) recorded for the summit on the OS 1:10,560 map, with the OS enlarged Geograph map giving a height of 391m for the extant col, thereby confirming that the hill used to have 37m of drop.  The summit has been quarried leaving the highpoint of the hill at c 417m (SE 120 641) on the western rim of the former summit dome, thereby reducing the drop to c 26m and relegating the hill to Sub-Four status. 

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 Cold Stones (SE 125 636) 

LIDAR analysis gives the highest ground on this hill as 421.2m positioned at SE 12584 63663 and 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 or Harvey 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 to the data produced by the Trimble or by LIDAR analysis.

Therefore, the new listed summit height of this hill is 421.2m and this was derived from LIDAR analysis, this is 4.2m higher than its previously listed height of c 417m which was based on interpolation of 5m contouring that appeared on the OS Maps website. 

 

The full details for the hill are:

Group:  Whernside

Name:  Cold Stones

OS 1:50,000 map:  99

Summit Height (New Height):  421.2m (LIDAR)

Summit Grid Reference:  SE 12584 63663 (LIDAR)

Col Height:  390.8m (LIDAR)

Col Grid Reference:  SE 11773 63538 (LIDAR)

Drop:  30.4m (LIDAR)

 

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

Myrddyn Phillips and Aled Williams (November 2022)

 

 

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