Thursday, 22 June 2017

Mapping Mountains – Hill Reclassifications – The Fours


The Fours – Hill Reclassifications

The Fours are the English hills at or above 400m and below 500m in height that have a minimum drop of 30m.  Accompanying the main P30 list are three sub lists; these are the 400m Sub-Four, 390m Sub-Four and 390m Double Sub-Four category’s, with their criteria detailed in the respective Change Registers that are linked in their above titles, with the Introduction to this list being linked in the above title.

The list is co-authored by Myrddyn Phillips and Aled Williams and the posts that have appeared on Mapping Mountains detailing the additions, reclassifications and deletions to the main P30 list and the sub lists appear below presented chronologically in receding order.









Mapping Mountains - Hill Reclassifications - The Fours

Reilth Top (SO 284 881) - Four reclassified to 400m Sub-Four (3rd reclassification)

Survey post for Reilth Top


There has been a reclassification to the listing of The Fours with a Four being reclassified to the ranks of 400m Sub-Four due to a survey with the Trimble GeoXH 6000.  The 400m Sub-Fours is one of three categories of sub hills that accompany the main The Fours list, with the criteria for Four status being all English hills at or above 400m and below 500m in height with 30m minimum drop, and the criteria for 400m Sub-Four status being all English hills at or above 400m and below 500m in height with 20m or more and below 30m of drop.

The hill is situated in the Beacon Hill group with its Cardinal Hill being Cilfaesty (SO 128 840) and is placed in Region 38, Section 38A Shropshire, and is positioned with the town of Bishop’s Castle towards its east.

The hill can be ascended from its south south-west or south-east where public footpaths give access to its lower slopes; however its summit is not a part of open access land so permission to visit should be sought.

The name of the hill is Reilth Top and prior to the survey with the Trimble GeoXH 6000 and its subsequent listing as a 400m Sub-Four it was listed as a Four with c 30m of drop based on an estimated summit height of c 406m with its uppermost summit contour on Ordnance Survey 1:25,000 Explorer maps being 405m, and an estimated col height of c 376m with col contouring between 375m – 380m.

The survey with the Trimble produced a summit height of 404.6m (converted to OSGM15) and a col height of 375.6m (converted to OSGM15), with these values giving this hill 29.0m of drop, which is insufficient for it to retain its Four status.


The full details for the hill produced by the Trimble are:


Cardinal Hill:  Cilfaesty

Summit Height:  404.6m (converted to OSGM15)

Name:  Reilth Top

OS 1:50,000 map:  137

Summit Grid Reference:  SO 28458 88105

Drop:  29.0m (converted to OSGM15)


Upon receiving the above details for confirmation of this hill’s reclassification Aled analysed LIDAR data and the details produced by the Trimble and LIDAR are given below:


Summit Height: 

404.6m (converted to OSGM15) at SO 28458 88105 for Trimble

404.6m at SO 28456 88108 for LIDAR



Col Height: 

375.6m (converted to OSGM15) at SO 28861 87869 for Trimble

375.3m at SO 28880 87845 for LIDAR



Drop:

29.0m for Trimble

29.3m for LIDAR


The col position and height being used is that produced by LIDAR data.


The overall total for The Fours is now 294 hills with two reclassifications, one each to 390m Sub-Four and 400m Sub-Four status since publication of the list by Europeaklist in December 2013.

The overall total for the 400m Sub-Fours is now 155 with this reclassification being to first addition to this sub category since publication of the list by Europeaklist in December 2013.

The list of Four hills is available from the Haroldstreet website (January 2014) with all subsequent changes detailed on the Mapping Mountains site.

For the additions and reclassifications to The Fours reported on Mapping Mountains since the December 2013 publication of the list by Europeaklist please consult the following Change Registers:







Gathering data at the summit of Reilth Top - now reclassified from a Four to a 400m Sub-Four

Myrddyn Phillips and Aled Williams (April 2017)







Mapping Mountains - Hill Reclassifications - The Fours

The Cold Piece (SO 338 996) - Four reclassified to 390m Sub-Four (2nd reclassification)

Survey post for The Cold Piece


There has been a reclassification to the list of The Fours due to a recent survey with the Trimble GeoXH 6000.  The hill is positioned in Shropshire and situated between Corndon and the Stiperstones.

The name of the hill is The Cold Piece (SO 338 996) and it appears under its Cardinal Hill of the Stiperstones on page 24 of The Fours booklet published by Europeaklist.  It is listed with an accompanying note (note number 256) which states:

‘As the only absolute height found for the summit of this hill is 1,311ft (399.6m) from the OS 1:10,560 map, doubt is cast upon its qualification as an English 400m P30, but as current mapping has a small uppermost 400m ring contour the hill remains in the list for now’

That was prophetic!

This now brings the overall total for The Fours to 295 hills with this being the first major alteration since publication of the list by Europeaklist in December 2013.  Since publication the sub category's accompanying the main P30 list have increased by two to 227 hills with the addition of West Nab (SK 266 939) which was discovered by Ed Gradwell and now the addition of The Cold Piece.

The hill is reclassified from The Fours list and will appear in the 390m Sub-Fours in the 2nd edition that will hopefully be published by Europeaklist.  The list of The Fours is also available from the Haroldstreet website.


The full details for the hill are:

Cardinal Hill:  Stiperstones

Summit Height:  399.5m (converted to OSGM15)

Name:  The Cold Piece

OS 1:50,000 map:  137

Summit Grid Reference:  SO 338 996

Drop:  57.5m (converted to OSGM15)


The Cold Piece (SO 338 996) reclassified from a Four to a 390m Sub-Four
For details on the survey that reclassified this hill from Four to 390m Sub-Four status please click {here}


Myrddyn Phillips and Aled Williams (2014)







Mapping Mountains - Hill Reclassifications - The Fours

West Nab (SK 266 939) - 390m Double Sub-Four addition (1st reclassification)


There has been an addition to the 390m Double Sub-Four category which has recently been discovered by Ed Gradwell, with the details forwarded by his brother; George.  The hill is West Nab (SK 266 939) and it is situated in the Peak District.

390m Double Sub-Fours are sought after rarities for list compilers as they fail to qualify for the main list of The Fours on two counts; height and prominence.  The Fours is published by Europeaklist and also available in bagging tick list format from the Haroldstreet website.


The full details for the hill are:


Cardinal Hill:  Bleaklow Head

Summit Height:  395m

Name:  West Nab

OS 1:50,000 map:  110

Summit Grid Reference:  SK 266 939

Drop:  c 23m


Ed Gradwell (L) and George Gradwell (R) at the featureless highest point of West Nab (SK 266 939).  Photo: David Gradwell

Myrddyn Phillips and Aled Williams (February 2014)

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