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 Thirty
First Group is Coed Gwent.
Coed
Gwent
East from the sea at ST 323 813
following the Afon Wysg (River Usk) to SO 359 092, continuing south of the
Clawdd Brook to bwlch at SO 396 129, continuing east of the Nant y Deri to SO 401
146, continuing south of the Afon Troddi (River Trothy) to SO 515 116,
continuing west of the Afon Gwy (River Wye) to the sea at ST 541 901. Bordering with Y Mynyddoedd Duon to the
north, Bryniau Cymoedd to the west, the sea to the south and the border with
England to the east.
Twmpau - 200m updates
Pt.
277m 277m ST 485 990
This hill was always a prime
candidate for promotion from the Sub-List as it has a 277m summit spot height,
and bwlch contouring between c 245m – c 250m, with the height of the bwlch
estimated as c 247m, giving this hill c 30m of drop. The hill was originally listed under the part
invented name of Devauden Hill; it now reverts to the Pt notation as the blog
author does not know an appropriate name for it.
Pt.
232m 232m SO 518 106
This hill has been promoted
from the Sub-List as it has a summit spot height of 232m and an estimated bwlch
height of c 202m, based on bwlch contouring between c 200m – c 205m, giving
this hill c 30m of drop. It was
originally listed as Troypark Wood Top which was partly based on the name of
the wood to the west of the summit, as this wood does not take in the high
point the name has been amended to the Pt notation as the blog author does not
know an appropriate name for it. The
name of Church Hill Common also appears on the lower south-easterly slope of
this hill on Ordnance Survey maps, as this name may just apply to a piece of
bounded land and not to the hill itself, it has not been used.
Sub-Twmpau - 200m updates
Trelleck
Hill c 288m SO 506 064
This hill has an uppermost ring
contour of c 285m and its height has been estimated as c 288m, the area of the
bwlch has a 261m spot height on the Ordnance Survey enlarged Geograph map at SO
510 057, although the positioning of this spot height is not centred on the
hill to hill traverse, contouring suggests it may be positioned near to the
critical bwlch, therefore this hill enters the Sub-List with c 27m of drop.
Gaer
Hill 264m ST 516 981
Another hill whose drop value
is dependent upon the Ordnance Survey enlarged Geograph map as both summit and
bwlch are spot heighted. The former has
a 264m spot height and the latter a 239m spot height, giving this hill a drop
of 25m.
Pt.
244m 244m ST 435 974
This hill follows the Pt.
notation for its name as no suitable name is known for it by the blog
author. The bwlch contouring is between
c 220m – c 225m, with the height of the bwlch estimated as c 222m and placed at
ST 433 972, giving this hill c 22m of drop.
Next update due on the 17th November 2014
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