Friday, 22 December 2023

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


Betchcott Hill (SO 421 982) 

There has been confirmation of 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 Betchcott Hill (SO 421 982)

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, 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 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 Betchcott Hill, 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 north-west and the A49 road farther to its east, and has the town of Church Stretton towards the south-east.

When the 1st edition of the The Fours was published by Europeaklist in December 2013, this hill was listed with 20m of drop and with a 414m summit height based on the spot height that appears on the contemporary Ordnance Survey 1:25,000 Explorer map and which is positioned at SO 420 982.  When the 2nd edition of the The Fours – The 400m Hills of England was published by Mapping Mountains Publications in April 2018, this hill had been surveyed with the Trimble GeoXH 6000, resulting in a 414.3m summit height positioned at SO 420 982.

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

However, it was not until LIDAR became available that the details for the summit of 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.

The raised field boundary on the summit of Betchcott Hill

LIDAR analysis gives the highest ground on this hill as 414.3m positioned at SO 42097 98234.  However, this is a part of a raised field boundary and protocols dictate that as this is deemed a relatively recent man-made construct such ground is discounted from the height of a hill.  

LIDAR summit image of Betchcott Hill (SO 421 982)

The height produced by LIDAR analysis to the natural summit of this hill is 414.2m positioned at SO 42106 98231, and this position in relation to the raised field boundary 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 LIDAR analysis is 414.2m and this is positioned at SO 42106 98231.  This position is close to where the 414m summit spot height appears on the contemporary Ordnance Survey 1:25,000 Explorer map and is approximately 9 metres eastward from the high point of the raised field boundary.

 

The full details for the hill are:

Group:  Stiperstones

Name:  Betchcott Hill

OS 1:50,000 map:  137

Summit Height:  414.2m (LIDAR)

Summit Grid Reference (New Position):  SO 42106 98231 (LIDAR)

Col Height:  394.3m (LIDAR)

Col Grid Reference:  SO 42922 97926 (LIDAR)

Drop:  20.0m (LIDAR)

 

Myrddyn Phillips and Aled Williams (December 2023) 

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