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

 

Wadsworth Moor (SE 015 283) 

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 Wadsworth Moor (SE 015 283)

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 Wadsworth Moor, and it is adjoined to the Pendle group of hills, which are situated in the southern Pennines, and it is positioned with a minor road to its south-west, the A6033 road farther to its west, and the A646 road farther to its south, and has the town of Hebden Bridge towards the south-west.

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

When the 2^nd 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 409m summit height, based on the spot height that appears on the Ordnance Survey 1:25,000 Explorer map.

A more accurate reflection of the summit height of this hill appears on the interactive DataMapWales

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 Wadsworth Moor (SE 015 283)

LIDAR analysis gives the highest ground on this hill as 411.95m positioned at SE 01573 28371, 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 411.95m and this was derived from LIDAR analysis, this position is relatively close to where the spot height appears, and is 2.95m higher than the previously listed 409m summit height, which appears as a spot height on the Ordnance Survey 1:25,000 Explorer map. 

 

The full details for the hill are:

Group:  Pendle

Name:  Wadsworth Moor

OS 1:50,000 map:  104

Summit Height (New Height):  411.95m (LIDAR)

Summit Grid Reference:  SE 01573 28371 (LIDAR)

Col Height:  390.0m (LIDAR)

Col Grid Reference:  SE 01164 29045 & SE 01166 29042 (LIDAR)

Drop:  22.0m (LIDAR)

 

Myrddyn Phillips and Aled Williams (June 2023)