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
Second Group is Moelfre.
Moelfe
North of the Afon Tywi
(River Towy) from SN 431 204 to SN 405 194, continuing north of the Tawelan
Brook to SN 393 195 and stream to Cors Goch and bwlch at SN 364 188 and the Nant
Coedcae to SN 325 178, continuing west of the Afon Cywyn to SN 307 129,
continuing north of the Afon Taf to SN 281 151, continuing east 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 south of the Afon Teifi to SN 411 401,
continuing south and then west of the Afon Tyweli and the Nant Grân
to bwlch at SN SN 419 337 and the Nant Aeron to SN 418 292, continuing north,
west and then south of the Afon Gwili to SN 431 204. Bordering with Mynydd Bach to the north, the
Elenydd to the east, Mynydd Sylen and Pen y Moelfre to the south and Brandy
Hill and Mynydd Preseli to the west.
Twmpau - 200m updates
Pt.
228m 228m SN 354 246
This hill was originally listed
in the Sub-List with the later addition of c 29m of drop. It was also listed under the name of Banc y
Maes y deri, which was a partly invented name based on buildings to the
north-west of the summit. The c 29m drop
value was based on a 227m height to a triangulation pillar which is given a
flush bracket height of 227.551m in the OS Trig Database and an estimated bwlch
height of c 198m, based on bwlch contouring between c 195m – c 200m. The hill now has an uppermost summit spot
height of 228m thanks to the Ordnance Survey enlarged Geograph map, the bwlch
contouring has been re-examined and the conclusion is as before, so this hill
now has a listed drop of c 30m. It is
also a P30 non TuMP (as of writing). The
hill name has reverted to the Pt. notation as no appropriate name is known for
it by the blog author.
Sub-Twmpau - 200m updates
Pt.
c 233m c 233m SN 288 289
The name of this hill follows
the Pt. notation as no suitable name is known for it by the blog author. The summit height has been estimated as c
233m, the area of the bwlch known as Rhos Pwllygawnen has a 209m spot height on
it on the Ordnance Survey enlarged Geograph map, and these values give this
hill c 24m of drop.
Pt. 224m 224m
SN 374 258
Another hill name that follows the Pt notation as
no appropriate name is known for it by the blog author. This hill has a 203m spot height on the area
of its bwlch that appears on the Ordnance Survey enlarged Geograph map, giving
this hill 21m of drop.
Pt. 217m 217m
SN 298 269
This hill qualifies for the Sub-List as it has a
196m spot height at its bwlch that appears on the Ordnance Survey enlarged
Geograph map. Its name follows the Pt.
notation and it is one of many that do so in the Welsh 200m Sub-P30 List. The summit value of 217m and bwlch value of
196m gives this hill 21m of drop.
Pt. 243m 243m
SN 322 274
An interesting hill as it was one of those that did
not qualify for the original Sub-List as its 243m summit and 223m bwlch spot
heights meant that it only had 20m of drop, and the original Sub-List was based
on hills that had a chance of P30 qualification after being surveyed.
Next update due on the 15th September 2014
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