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 first Group
is the Carneddau.
Carneddau
North of the Afon Denau /Afon
Ogwen and Afon Llugwy / Afon Conwy (centred on SH 675 604), north-east from Traeth
Lafan at SH 610 721 and south-west from Conwy Bay at SH 774 791. Bordering with the Glyderau to the south and
Mynydd Hiraethog to the east.
Twmpau - 200m updates
Y
Pincin 264m SH 723 581
This is a small rocky hill that
overlooks Capel Curig and can be joined with an ascent of Crimpiau (SH 732 595)
and the higher hills to the north. The
hill has been surveyed with the Trimble GeoXH 6000 as 263.5m summit and 228.8m
bwlch, giving this hill 34.7m of drop.
Sub-Twmpau - 200m updates
Pt.
248m 248m SH 784 580
This is a forested summit to the north-west of
Betws-y-coed. Dependent upon the density
of the conifers this hill may be a good candidate to survey with the Trimble
for P30 status as it is listed with c 29m of drop.
Pt.
c. 236m c 236m SH 750 777
The summit of this hill appears
where the 5m contour intervals revert to 10m contour intervals on the large scale Ordnance Survey mapping on
the Geograph website. However, the
uppermost c 235m contour is evident and the summit has been estimated as c
236m. The height of the bwlch has been
estimated as c 213m, giving c 23m of drop.
Pt.
253m 253m SH 788 583
This is another forested summit to the north of
Betws-y-coed. It has an estimated bwlch
height of c 232m, giving c 21m of drop.
Next update due on the 21st April 2014
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