Foel (SH 450 506) – Subhump reclassified to Hump
This is the seventeenth 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.
Foel (SH 450 506) |
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, or in this instance
from a survey with the Trimble GeoXH 6000, and for the reclassifications that
affected the Humps the first survey
of this hill took place on the 30.12.13.
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 a reclassification to the listing of the Humps (HUndred Metre Prominences) instigated
by a survey with the Trimble GeoXH 6000 and which was later confirmed by a
survey with the Leica GS15.
Prior to the survey with the Trimble GeoXH 6000 Mark Jackson
had listed this hill as a Subhump
with c 99m of drop based on the 223m summit spot height that appears on the Ordnance
Survey 1:25,000 Explorer map and an estimated bwlch height of c 124m based on
bwlch contouring at 10m intervals.
The hill is adjoined to the Moel Hebog group of hills and is
situated overlooking the A 487 road which is to its east and the Afon Llyfni
which is to its north, with the small community of Pen-y-groes to the north-east
and Clynnog Fawr to the west south-west.
Foel was surveyed using a Trimble GeoXH 6000 by Myrddyn
Phillips on the 30.12.13 resulting in a 100.9m drop value, the hill was then
re-surveyed with the Trimble GeoXH 6000 on the 02.02.14 resulting in a 101.6m
drop value, it was then again re-surveyed on the 16.02.14 by John Barnard,
Graham Jackson and Myrddyn Phillips using a Leica GS15 and Trimble GeoXH 6000
resulting in a 101.2m and 101.1m drop value respectively, which is sufficient
for this hill to be reclassified from Subhump
to Hump status.
The reclassification of this hill from Subhump to Hump status was accepted by Mark Jackson
and its new classification augmented in to the listing of the Humps in February 2014.
Gathering data with the Trimble GeoXH 6000 at the summit of Foel |
The full details for the hill are:
Name: Foel
Summit Height: 221.3m (as
listed in the Humps, 221.4m converted to OSGM15)
OS 1:50,000 map: 115,
123
OS 1:25,000 map: 254
Summit Grid Reference:
SH 45025 50677
Drop: 101.2m (converted to OSGM15)
Myrddyn Phillips (October 2017)
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