Mapping Mountains – Hill Reclassifications – Humps

Gray Hill (ST 433 935) – Subhump addition

This is the ninth in a series of Hill Reclassification posts that detail hills whose status has been altered in the listing of the Humps (HUndred Metre Prominences) through map study and / or surveys that I have instigated.

The hill name used in this and forthcoming posts is that used in the listing of Humps, therefore individual names and their composition may not match those that are used in listings I am directly associated with.  However, I am of firm belief that listed hill names used by other authors should be respected when giving detail within other people’s lists, however inappropriate some hill names may be considered.

This and forthcoming posts are retrospective as many of these hill reclassifications were initiated from studying the Ordnance Survey enlarged mapping that is hosted on the Geograph website, and for the reclassifications that affected the Humps the email I posted on the RHB Yahoo Group forum in relation to this hill was dated 18.05.12.

The listing of Humps was published in book format by Lulu in 2009 and entitled More Relative Hills of Britain, its author; Mark Jackson gives credit to a number of people who contributed toward the formation of this list, these include; Eric Yeaman, Alan Dawson, Clem Clements, Rob Woodall, Bernie Hughes, Pete Ridges and others.  When the list was published in book format there were 2987 Humps listed with their criteria being any British hill that has 100m or more of drop, accompanying the main list is a sub category entitled Subhumps, with the criteria being any British hill that has 90m or more and below 100m of drop.

More Relative Hills of Britain by Mark Jackson

The details for the reclassification appear below:

There has been an addition to the listing of the Humps (HUndred Metre Prominences) due to consulting the Ordnance Survey enlarged mapping that is hosted on the Geograph website, with these details being posted on the RHB Yahoo Group forum on 18.05.12.

Prior to this notification Mark Jackson had listed this hill with c 39m of drop based on the 273m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map (whilst the Ordnance Survey 1:50,000 Landranger map has a summit spot height of 275m which is the rounded metric equivalent of the 902ft height that appears on the Ordnance Survey Six-Inch map) and an estimated bwlch height of c 234m, with this latter height an obvious error as the bwlch contouring is between 180m – 185m.  The area of the bwlch benefits from having contour intervals at 5m and a 182m spot height on a road on the Ordnance Survey enlarged mapping on the Geograph website.  With this latter height or an estimated bwlch height of c 183m giving this hill c 90m – 91m of drop if the 273m summit height on the 1:25,000 map is followed, or alternatively c 92m – 93m of drop if the 275m summit height on the 1:50,000 map is followed, whichever value is chosen it is sufficient for this hill to be classified as a Subhump. 

Extract from the Ordnance Survey enlarged mapping hosted on the Geograph website that shows the 273m summit and 182m bwlch spot heights

The hill appears under the name of Gray Hill in the listing of the Humps, this name appears on current Ordnance Survey maps, but for its originator name the Ordnance Survey Draft Surveyors map and the Ordnance Survey One-Inch ‘Old Series’ map have to be consulted, and on each the name Mynydd Llwyd appears.  The Welsh name for this hill is considered more appropriate than its English counterpart (see Language sub heading under Prioritised Decision in the Naming Protocols within the Protocols for the Naming of Hills document).

Extract from the Ordnance Survey Draft Surveyors map giving the hill its Welsh name of Mynydd Llwyd

Extract from the Ordnance Survey One-Inch 'Old Series' map which also gives this hill its Welsh name of Mynydd Llwyd

The hill is adjoined to the Coed Gwent range of hills and is situated overlooking the Wentwood Reservoir which is to its south-west, with the village of Llanfaches (Llanvaches) towards the south.

The addition of this hill to Subhump status was accepted by Mark Jackson on the 19.07.12 and the listing of the Humps was updated accordingly.

The full details for the hill are:

Name:  Gray Hill (as listed in the Humps)

Summit Height:  273m (as listed in the Humps)

OS 1:50,000 map:  171, 172

OS 1:25,000 map:  14

Summit Grid Reference:  ST 43399 93559

Drop:  c 90m (as listed in the Humps)

Myrddyn Phillips (September 2017)