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

 

Nipstone Rock (SO 356 969) 

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 a Trimble GeoXH 6000 survey conducted by Myrddyn Phillips. 

Nipstone Rock (SO 356 969)

The criteria for the list this height revision affects 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 list are three categories of sub hills, with this hill being included in 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 Nipstone Rock, and it is adjoined to the Stiperstones group of hills, which are situated in the county of Shropshire close to the Welsh border, and it is positioned encircled by minor roads with the A488 road farther to its west, and has the small community of White Grit towards the west.

When the 1^st edition of the The Fours was published by Europeaklist in December 2013, this hill was listed with an estimated c 22m of drop, with an estimated c 445m summit height positioned at SO 356 969 based on interpolation of the uppermost ring contour that appears on the contemporary Ordnance Survey 1:25,000 Explorer map and an estimated c 423m col height, based on interpolation of contouring between 420m – 425m. 

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

However, it was not until the Trimble GeoXH 6000 survey that an accurate height for both the main summit of Nipstone Rock and its adjacent heather clad summit could be determined.  This survey gives the highest ground on this hill as 447.0m positioned at SO 35668 96957 on the main Nipstone Rock summit , as opposed to 445.4m positioned at SO 35563 96815 to the adjacent heather clad summit, 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. 

The Trimble GeoXH 6000 gathering data at the summit of Nipstone Rock

The Trimble GeoXH 6000 gathering data at the adjacent heather clad summit

Therefore, the new listed summit height of this hill is 447.0m and this was derived from a Trimble GeoXH 6000 survey, 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 2.0m higher than the previously estimated c 445m summit height which was based on interpolation of the uppermost ring contour that appears on the Ordnance Survey 1:25,000 Explorer map. 

 

The full details for the hill are:

Group:  Stiperstones

Name:  Nipstone Rock

OS 1:50,000 map:  137

Summit Height (New Height):  447.0m (converted to OSGM15)

Summit Grid Reference:  SO 35668 96957

Col Height:  423.9m (converted to OSGM15)

Col Grid Reference:  SO 36160 97549

Drop:  23.0m

 

Myrddyn Phillips and Aled Williams (December 2023)