Mapping Mountains – Hill Reclassifications – The 500-Metre Tops of England and Wales – Deweys

Beardown Tors (SX 602 773) – Dewey addition

This is one in a series of retrospective Hill Reclassification posts that detail hills whose status has altered in the listing of the Deweys and where I have had direct association with the status change.  These posts will tie in with a forthcoming Change Register giving detail to this list and its alterations since publication in the Mountain tables book.

LIDAR image of Beardown Tors (SX 602 773)

The 500-Metre Tops of England and Wales are affectionately known after their hill list compiler; Michael Dewey.  This list mixes metric and imperial height in its criteria to bookend up to the 2000ft height band and takes in all hills in England, Isle of Man and Wales that are 500m and above and below 2000ft (609.6m) in height that have 30m minimum drop.

This list formed one of a number of lists that appeared in the Mountain tables book published by Constable in 1995 and at the time of publication comprised 373 hills with 164 in England, 5 in the Isle of Man and 204 in Wales.  The Deweys have undergone extensive revision since first publication with the initial stages forming the basis of this revision given below:

1995    Mountain tables published by Constable with 373 hills listed as Deweys.

April 2000    Strider (LDWA quarterly booklet) publishes contact details for David Purchase and Myrddyn Phillips who have found and list 24 and 14 possible new 500m tops respectively.

It was expanded versions of the above two lists that formed the basis of the next publication:

25^th May 2000    List of Possible 500 Metre Tops by Michael Dewey listing 44 hills.

David Purchase expands his Additional Dewey 500m Hills and Myrddyn Phillips produces lists of English 500m hills to measure and Welsh 500m hills to measure.

These lists formed the basis of the next publication:

29^th June 2000    Possible/Probable 500’s by Michael Dewey listing 77 hills.  Michael adopts following protocol; if one person proposes that a top should qualify as a 500 by personal survey, and is then confirmed by a second person, it should then be promoted to the main list.

April 2002    The 500+ Tops of England and Wales – The ‘New Deweys’ published in the Strider booklet and listing 66 new qualifying hills.

25^th May 2006    Rob Woodall republishes Michael’s main and possible/probable lists on the RHB Yahoo group file database. 

Mountain tables by Michael Dewey

The details for this addition appear below:

The name the hill is listed by in the Deweys is Beardown Tors, and it is adjoined to the Dartmoor group of hills which are situated in the south-west of England, and it is positioned with the A386 road to its west, the B3357 road to its south-west and the B3212 road to its east, and has the town of Tavistock towards the west.

This hill was not included in the original 1995 Constable publication, but with a 513m summit spot height and col contouring between 480m – 490m that appear on the Ordnance Survey 1:25,000 Explorer map, the interpolated drop value was estimated sufficient for this hill to be a potential new Dewey as the opposing 480m ring contours are relatively close together.

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

The above detail was noted by David Purchase and Myrddyn Phillips who worked independently but also exchanged all data, with David assessing the hill’s qualification on site.  These details were forwarded to the list author; Michael Dewey and the hill was added to the list on the 28^th July 2001.

Since the inclusion of this hill in the Dewey list the Ordnance Survey Vector Map Local hosted on the Geograph website and which is entitled the Interactive Coverage Map became available online.  This mapping had many spot heights not on other publicly available Ordnance Survey maps and gave a 481m col spot height, and when coupled with the 513m summit spot height, these values gave this hill 32m of drop.

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 Beardown Tors

LIDAR col image of Beardown Tors

The summit and col height for this hill were subsequently ascertained from LIDAR analysis conducted by Myrddyn Phillips, resulting in a 512.4m summit height and a 480.9m col height, with these values giving this hill 31.6m of drop and therefore confirming its Dewey status. 

The full details for the hill are:

Name:  Beardown Tors

OS 1:50,000 map:  191

OS 1:25,000 map:  28

Summit Height:  512.4m (LIDAR)

Summit Grid Reference:  SX 60285 77312 (LIDAR)

Col Height:  480.9m (LIDAR)

Col Grid Reference:  SX 60251 77961 (LIDAR)

Drop:  31.6m (LIDAR)

Myrddyn Phillips (August 2020)