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 eighth
Group is Bryniau Clwyd.
Bryniau
Clwyd
North from the Afon Dyfrdwy
(River Dee) and the border with England at SJ 317 395 to SJ 066 429 and then
south and west of the Afon Camddwr to the Fish Pond at Y Rug (SJ 056 438),
continuing west of the Afon Camddwr to bwlch at SJ 069 477 and the Afon Clwyd
at SJ 071 500 to the sea at SJ 997 808.
Bordering with Y Berwyn to the south, Mynydd Hiraethog to the west, the
sea to the north and the English border to the east.
Twmpau - 200m updates
Billins
294m SJ 195 719
This hill is part of Halkyn Mountain and is a
promotion from the sub-list as the hill has a summit triangulation pillar with
a flush bracket height of 294.281m (293.981m to base of trig approximately) and
a bwlch estimated as c 263m with contours between c 260m – c 265, giving the hill
c 31m of drop. There are two options for
the position of the bwlch, both are estimated as c 263m high, they are situated
at SJ 203 708 and SJ 208 700.
Pen y Ball 258m
SJ 173 756
This hill was not included in the original 200m P30
list. The bwlch contouring is between c
225m – c 230m with the height estimated as c 227m, giving a drop of c 31m. However, the summit consists of a mound that
overlooks Holywell and has a monument on it that commemorates the
marriage, coronation and silver jubilee of George V. I do not know if the mound is man-made, if it
is, it would exclude this hill from the P30 list as the drop would then be
insufficient to qualify.
Coed
Pen-y-gelli 233m SJ 135 762
A promotion from the sub-list and a summit that is
twinned with Coed Moel-dda at SJ 143 754, both summits are given a 233m black
spot height on the Ordnance Survey 1:25,000 map. The bwlch contouring for Coed Pen-y-gelli is
between c 200m – c 205m and has been estimated as c 203m, giving a drop of c
30m. The bwlch separating the twin
summits has been estimated as c 218m, giving the non-prioritised summit of Coed
Moel-dda a drop of c 15m.
Pt. 213m 213m
SJ 304 530
This is a summit relocation from the 211m hill
previously listed by the invented name of Moss Hill at SJ 301537. The new summit has a 213m spot height on the
Ordnance Surveyed enlarged Geograph map.
The point notation has been used for its name as no appropriate name is
known for the hill.
Sub-Twmpau - 200m updates
Moel
Ffagnallt 289m SJ 189 700
A hill that has recently been
surveyed with the Trimble GeoXH 6000, the Ordnance Survey map has a summit spot
height of 287m and the bwlch contouring is between c 260m – c 265m.
Pt.
257m 257m SJ 096 720
This hill has a summit spot
height of 257m on the Ordnance Survey enlarged Geograph map and bwlch
contouring between c 230m – c 235m, with an estimated height of c 233m, giving
a drop of c 24m. There is also an
adjacent ‘Mound’ that has an uppermost ring contour of c 255m at SJ 096 719.
Pt.
208m 208m SJ 159 728
With a summit spot height of
208m and an estimated bwlch height of c 184m this hill qualifies for the Sub
list with c 24m of drop.
Craig
y Rhos 299m SJ 149 435
The bwlch is placed at SJ 149
437 and has a 276m spot height on the Ordnance Survey enlarged Geograph map,
giving this hill 23m of drop.
Pt.
c 285m c 285 SJ 206 703
With an estimated summit height
of c 285m and an estimated bwlch height of c 263m, with bwlch contouring
between c 260m – c 265m, this hill has an estimated c 22m of drop.
Pt.
214m 214m SJ 152 737
The name of Bryn Glas appears
close to the summit of this hill on Ordnance Survey maps but it is probably the
name of the farm to the south-east of this hill’s summit, therefore the point
notation has been used for the name of the hill. The hill has a summit triangulation pillar
with a flush bracket height of 214.344m in the OS Trig Database. The bwlch contouring is between c 190m – c
195m, with an estimated height of c 192m, giving a drop of c 22m.
Pt.
295m 295m SJ 088 469
With a summit height of 295m
and an estimated bwlch height of c 274m at SJ 091 472, this hill is a new
addition to the Sub list with an estimated c 21m of drop.
Bryn
Digrif 217m SJ 126 792
This hill has a summit spot
height of 217m and a bwlch spot height of 196m at SJ 129 788, giving the hill
21m of drop.
Pt.
267m 267m SJ 090 463
The bwlch contouring for this
hill is centred on SJ 092 466 and is between c 240m – c 250m, with an estimated
height of c 247m, giving a drop of c 20m.
Glol 232m
SJ 120 781
The Ordnance Survey enlarged
Geograph map has a 212m spot height at SJ 172 782 which is at a road
junction. Although not centred on the
valley to valey traverse the estimated bwlch height would be c 212m at SJ 128
781. Therefore the hill enters the Sub
list with a drop of c 20m.
Next update due on the 9th June 2014
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