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 thirteenth
Group is Cadair Idris.
Cadair
Idris
North of Aber Dysynni at
SH 560 030 and the Afon Dysynni to Llyn Mwyngil (Tal y Llyn Lake) at SH 710
094, continuing north from SH 720 103 following the Afon Faw, Afon Fawnog and
Nant yr Allt-oen to bwlch at SH 756 139, continuing west and then south of the
Afon Clywedog to SH 748 188, continuing south of the Afon Wnion to SH 711 190
and the Afon Mawddach to Bae Abermaw (Barmouth Bay) and the sea at SH 603 147. Bordering with the Rhinogydd and Arennig to
the north, Aran and Bryniau Dyfi to the east, Tarennydd to the east and south
and the sea to the west.
Twmpau - 200m updates
Craig y Castell 298m
SH 694 172
A hill that has always been a prime candidate for
promotion from the Sub-List and as the Ordnance Survey enlarged Geograph map
has a summit spot height of 298m and a bwlch spot height of 264m, this hill has
34m of drop and joins the ranks of P30’s.
Craigymerwydd 296m
SH 644 134
Another prime candidate for promotion and with the
bwlch height estimated as c 263m from contouring between c 260m – c 270m, it
gives this hill c 33m of drop.
Tลตr Glas
228m SH 672 164
The hill is situated in a lovely area of the Cadair
Idris range and is positioned just to the north of Llyn Wylfa. It has been promoted from the Sub-List as the
Ordnance Survey enlarged Geograph map gives it a summit spot height of 228m and
the bwlch height has been estimated as c 196m, giving this hill c 32m of
drop. The enlarged Geograph map also
spots another height in the vicinity of the summit as 227m at SH 673 165.
Gribin 211m
SH 675 168
This hill is an automatic entry to the list of
Welsh 200m P30 hills and was mistakenly listed in the Sub-List when first
published. The hill now has a summit
spot height of 211m thanks to the Ordnance Survey enlarged Geograph map. The bwlch contouring is between c 170m – c
180m, and has been estimated as c 172m, giving this hill c 39m of drop.
Sub-Twmpau - 200m updates
Pt. 297m 297m
SH 694 169
The Pt. notation has been used for the name of this
hill as no appropriate name is known by the blog author. This hill has a 297m summit and a 271m bwlch
spot height on the Ordnance Survey enlarged Geograph map, giving this hill 26m
of drop. The hill has a twin summit at
SH 693 171 that also qualifies for Sub status.
Pt. 297m 297m
SH 693 171
The Pt. notation has been used for the name of this
hill as no appropriate name is known by the blog author. This hill has a 297m summit and a 272m bwlch
spot height on the Ordnance Survey enlarged Geograph map, giving this hill 25m
of drop. The hill has a twin summit at
SH 694 169 that also qualifies for Sub status.
Dolgledr 256m
SH 690 175
The summit spot height is taken from the Ordnance
Survey enlarged Geograph map, whilst the bwlch height is estimated as c 234m at
SH 689 174 from contouring between c 230m – c 240m, giving this hill c 22m of
drop.
Pt. 274m 274m
SH 654 140
As no appropriate name is known for the hill by the
blog author the Pt. notation is being used.
The summit has a 274m spot height on the Ordnance Survey enlarged
Geograph map and the bwlch contouring is between c 250m – c 260m. There is a 254m spot height on the narrow
road on the enlarged Geograph map at SH 659 139, but the bwlch contouring
suggests that the critical bwlch may be lower than this and placed at SH 658
140. However, the 254m spot height and
position is being taken for the drop value, which gives this hill 20m of
prominence.
Next update due on the 14th July 2014
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