Saturday 1 August 2020

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


THIS HILL HAS SUBSEQUENTLY BEEN DELETED FROM THE DEWEY LIST


Birks Fell (SD 919 761) – 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.

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:

25th 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:

29th 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.

25th 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 Birks Fell, and it is adjoined to the Ingleborough group of hills which are situated in the Yorkshire Dales in England, and it is positioned with the A684 road to its north, the B6479 road to its west, the A65 road to its south and the B6160 road to its east, and has the town of Settle towards the south-west.

This hill was not included in the original 1995 Constable publication, but as it was not included at the time in the 2000ft (609.6m) hill lists of Nuttalls (P15) and Hewitts (P30) it was prudent that it should be included as a Dewey.  However, it did possess a 610m summit spot height on the Ordnance Survey 1:50,000 Landranger map.

Extract from the Ordnance Survey 1:50,000 Landranger 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 28th July 2001.

This hill had been proposed for inclusion as a Nuttall and Hewitt by several people, most notably John Barnard and Graham Jackson who on the 3rd June 2006 used an automatic level in calculating the height of this hill.  The Ordnance Survey subsequently confirmed its height as over 609.6m resulting in its deletion from Dewey status.

LIDAR summit image of Birks Fell

LIDAR col image of Birks Fell

The summit and col heights for this hill were subsequently ascertained from LIDAR analysis conducted by Myrddyn Phillips.  The LIDAR (Light Detection & Ranging) technique produced highly accurate height data that is now freely available for much of England and Wales.  This analysis resulted in a 610.3m summit height positioned at SD 91879 76371 and a 452.2m col height positioned at SD 83648 76034, with these values giving this hill 158.1m of drop, confirming its deletion from Dewey status.


The full details for the hill are:

Name:  Birks Fell

OS 1:50,000 map:  98

OS 1:25,000 map:  30

Summit Height:  609m (as listed in the Deweys)

Summit Grid Reference:  SD 919 761 (as listed in the Deweys)

Col Height:  452m (spot height)

Col Grid Reference:  SD 83627 76052 (spot height)

Drop:  157m


Myrddyn Phillips (August 2020)


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