The first list to the Welsh
200m P30 hills was published on Geoff Crowder’s website v-g.me in 2000; this
list preceded the list of TuMPs by nine years, the list proved a very useful
resource for the TuMP compilation for this category of hill.
The Welsh 200m P30 list
documents all hills in Wales that are at or above 200m in height and are below
300m in height, to qualify for the main list each hill requires a minimum of
30m of prominence.
The hills listed below are
updates to the Welsh 200m P30 list originally published on Geoff Crowder's
website. To see the original list click {here}
The original published list had
a Sub-List which was entitled ‘Hills to Survey’. This list consisted of all hills in Wales in
the stipulated height band that have a minimum of 20m of prominence, but do not
meet the minimum 30m of prominence to enter the main list, according to
Ordnance Survey map spot heights and contours.
Nowadays the standard Sub-List takes in all hills that have a minimum of
20m of prominence. However, the Hills to
Survey Sub-List discounted hills whose map spot heights gave a drop value of
less than 30m, but more than 20m. By
doing so, the only hills that were Sub-Listed were those that map values
dictated stood a chance of entering the main list, for example; if a hill had a
summit spot height of 250m and a bwlch spot height of 221m, it was not listed
in the Hills to Survey Sub-List as with 29m of drop I thought it did not stand
a chance of main list qualification.
When compiling the Sub-List I
was measuring many hills for P30 status using a basic levelling technique,
please click {here} for more information concerning this. I now know that Ordnance Survey spot heights
have a standard margin of uncertainty of + / - 3m associated with their
accuracy. Therefore many hills that were
not listed in the original Sub-List may have sufficient drop to enter the main
list. Because of this the Sub-List has
been altered to include all hills that have a minimum of 20m of drop but are
not known to attain the minimum 30m of drop to enter the main list.
The hills listed below are
those major amendments to the original Welsh 200m P30 list as it appears on
Geoff’s website. There are many hills
that have been promoted from the Hills to Survey Sub-List to the main list,
whilst there are many additions to the Sub-List now that it has been
standardised to include all 20m minimum but below 30m drop hills.
When the 200m P30 list was
first published it was the first to this category of hills and in some way it
and its other 100m height band lists paved the way for Clem’s data that later
appeared on the RHB file database and then for the TuMPs listing by Mark
Jackson.
As well as the first P30 list
to this height band the list is now the first to include a comprehensive
Sub-List.
TuMP baggers beware; as the
main list also includes P30’s not listed by Mark Jackson, so if you want to
visit all P30’s you’ll have to include some non TuMPs to do so.
The list will be updated on a
weekly basis and will be done so through each Group category, starting from the
north and working south. The Twenty
Fourth Group is Mynydd Preseli.
Mynydd
Preseli
East from Aber Mawr at
SM 881 345 following stream to bwlch at SM 888 319 and the Western Cleddau at
SM 892 316 to SM 957 152, continuing north of the Cartlett Brook to bwlch at SN
018 194 and the Church Hill Brook and the Deepford Brook to SN 071 198, continuing
north of the Afon Syfni to SN 084 194, continuing east of the Cleddau Ddu
(Eastern Cleddau) to SN 075 166, continuing north of stream to bwlch at SN 142
179 and the Afon Daulan to SN 162 186 and Afon Taf to SN 281 151, continuing west
of the Afon Cynin to SN 261 286, the Afon Asen to bwlch at SN 254 317 and the
Afon Pedran and Afon Cych to SN 245 414, continuing west of the Afon Teifi to SN
158 492. Bordering with Carn Llidi to
the west, Brandy Hill to the south, Moelfre and Mynydd Bach to the east and the
sea to the north.
Sub-Twmpau - 200m updates
Mynydd
Bach 293m SN 108 290
The area of the summit has a
triangulation pillar on it, which has an adjoined flush bracket that is given
the height of 293.827m in the OS Trig Database.
The bwlch contouring is between c 265m – c 270m and has been estimated
as c 268m high, giving this hill c 25m of drop.
Goetty
Mountain 287m SN 068 292
The Ordnance Survey map
indicates that land adjacent to this hill’s summit is named Budloy
Mountain. The area of the bwlch has a
264m spot height at SN 072 293 on Ordnance Survey maps at a road junction,
interpolation suggests this position is a little too high for the ctitical
bwlch. Therefore the bwlch height has
been estimated as c 262m and positioned at SN 073 293, based on bwlch
contouring between c 260m – c 265m
Bernard’s
Well Mountain 272m SN 055 291
Bwlch contouring is between c
245m – c 250m and has been estimated as being c 248m high and positioned at SN
050 290. There is a 246m spot height on
a road positioned at SN 050 291 on Ordnance Survey maps, this is considered as
being too low. The 272m summit and c
248m bwlch values give this hill c 24m of drop.
Pt.
241m 241m SN 174 388
The listed name for this hill
follows the Pt. notation as no appropriate name is known for it by the blog
author. There seems to be an anomaly
between the current 240m spot height on Ordnance Survey maps adjoined to the
summit’s triangulation pillar and the details in the OS Trig Database, which
give the flush bracket height on the trig as 241.429m, indicating that ground
at the base of the trig is just over 241m high.
The bwlch contouring is between c 215m – c 220m and has been estimated
as c 217m, giving this hill c 24m of drop.
Pt.
217m 217m SN 253 364
Another hill name that follows
the Pt. notation as the blog author does not know an appropriate name for the
hill. The bwlch contouring is between c
190m – c 195m and has been estimated as being c 193m high, giving this hill c
24m of drop.
Pt.
263m 263m SN 225 333
The name of this hill follows
the Pt. notation as the blog author does not know an appropriate name for the
hill. The bwlch has a 242m spot height
on it at SN 226 340 which has been taken as the height of the bwlch, the area
of the bwlch also has a 244m spot height at SN 225 338 that appears on the
Ordnance Survey enlarged Geograph map, this is considered to be positioned too
high for the critical bwlch. The 263m
summit and 242m bwlch values give this hill 21m of drop.
Pt.
220m 220m SM 990 302
As the blog author does not
know a suitable name for this hill, its listed name follows the Pt.
notation. The bwlch contouring is
between c 195m – c 200m and its height has been estimated as c 199m, giving
this hill c 21m of drop.
Next update due on the 29th September 2014
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