Hill
Lists – Cymru / Wales
Twmpau
– 700m P30s
Introduction
To
access the Twmpau – 700m P30 list please click {here}
Diffwys in the Rhinogydd - one of the 700m Twmpau hills |
The first published lists to the P30 hills under the 500m height band were made available on Geoff Crowder’s v-g.me website in 2002 and 2003. These hills appeared in five separate lists and were split into 100m height bands. As their titles imply the listings are to hills in Wales; they are:
The Welsh 400 Metre Peaks
The Welsh 300 Metre Peaks
The Welsh 200 Metre Peaks
The Welsh 100 Metre Peaks
The Welsh 30-99 Metre Peaks
These listings were envisaged
as part of an accumulated list taking in eleven separate lists in all. The remaining six lists are to the 100m
height bands above 500m with the final list being to the Welsh 1000m P30 hills. Although these lists were prepared for
publication, they were never submitted as their respective hills had already
been published in the combined lists of the Deweys and Hewitts, which were
available on Geoff’s v-g.me website.
The advent of the Mapping Mountains
blog now enables me to fulfil my original concept and publish the six remaining
lists.
The accumulated list taking in
all eleven 100m height band lists and therefore all the Welsh P30s has now been
named ‘Twmpau’. The Welsh word ‘twmpath’ is translated as ‘hillock’,
which is an apt description for many of the hills in the combined list, and has
been used as ‘twmp’ in certain parts
of Wales, with the literal translation of the word being ‘tump’. Although the Welsh word twmp forms part of this list’s name, the name ‘Twmpau’ is an
acronym and stands for ‘thirty welsh metre prominences and upward’. This title also pays due deference toward the
name and acronym coined by Gary Honey and Jon Foote respectively for the list
by Mark Jackson that was made available on the Yahoo Group RHB file database in
2009, which relied upon much of its data for Welsh hills from the lists
published on Geoff Crowder’s v-g.me website and the RHB file database.
Brief History:
Many Welsh hill lists evolve
from their previous counterparts and the Twmpau is no different as the use of
30m, or its whole numbered imperial equivalent of 100ft can be traced back to
1925 when Carr and Lister used 100ft of drop in their list to ‘The Mountains of
Snowdonia’. It would be another 59 years
before Terry Marsh used the metric whole numbered equivalent of 30m as a drop
value in ‘The Summits of Snowdonia’.
Others have followed, some of note are Tony Blackburn (1985, The 500
Metre Tops of England and Wales), Kevin Borman (1990, The Mountains of Wales),
Alan Dawson (1992, The Absolute Summits of England and Wales [Sweats] later to
become; 1997, The Welsh Hewitts) and Michael Dewey (1995, The 500-Metre Tops of
England and Wales).
The above P30 listings were
expanded downwards in absolute height by ‘Clem’ Clements and Myrddyn Phillips,
who worked independent of one another.
Clem listed down to 100m in absolute height and included Sub hills down
to P27m, whilst Myrddyn listed down to 30m in absolute height and included Sub
hills down to P20m. The first of these
independently compiled lists to be published were the Myrddyn Phillips lists,
appearing on Geoff Crowder’s v-g.me website, with the 400m P30 list also
appearing on the RHB file database. This
was eventually followed by the uploading of ‘Clem’ Clements’ lists on the file
database of the RHB Yahoo Group. It was
these two lists that formed the basis for the majority of Welsh Tumps listed by
Mark Jackson in 2009.
Much of this data concerned
hills that were unnamed on current maps and were in fact, listed by names
invented by the hill list author.
Unfortunately, many of these names as a result, found their way into the
current listing of the Tumps. The names
of hills listed in the Twmpau will not rely upon invented names that have no
local or historical evidence of use and the author will endeavour to use the
most appropriate composition for each hill name.
In summary, the first published
lists using 100ft / 30m of drop appear below, all except for the Carr and
Lister publication use height bands that are within the Twmpau. These lists were compiled by:
1925 Carr and Lister The Mountains of Snowdonia. 2,000ft minimum height with 100ft minimum
drop.
1984 Terry Marsh The Summits of Snowdonia. 600m minimum height with 30m minimum drop.
1985 Terry Marsh The Mountains of Wales. 600m minimum height with 30m minimum drop.
1995 Michael Dewey Mountain tables The 500-Metre Tops of England and
Wales. 500m minimum height with 30m
minimum drop.
2002 Myrddyn Phillips The Welsh 400 Metre Peaks. 400m minimum height with 30m minimum drop.
2003 Myrddyn Phillips The Welsh 300 Metre Peaks. 300m minimum height with 30m minimum drop.
2003 Myrddyn Phillips The Welsh 200 Metre Peaks. 200m minimum height with 30m minimum drop.
2003 Myrddyn Phillips The Welsh 100 Metre Peaks. 100m minimum height with 30m minimum drop.
2003 Myrddyn Phillips The Welsh 30-99 Metre Peaks. 30m minimum height with 30m minimum drop.
The 700m P30 list documents all
hills in Wales that are at or above 700m in height and below 800m in height, to
qualify for the main list each hill requires a minimum of 30m of prominence.
Any accompanying Sub-List
includes all hills in Wales that have a minimum of 20m of drop but are not
known to attain the minimum 30m of drop to enter the main list.
To
access the Twmpau – 700m P30 list please click {here}
Moel Eilio - forms part of an extended ridge leading to the summit of Yr Wyddfa |
The list consists of the following:
Group: Each hill appears under their Group, this is
the group / range that the hill is a part of.
For example; Pen Llithrig y Wrach (SH 716 622) is part of the hill group
known as the Carneddau. The Groups are
arranged from north to south on a west to east orientation.
Name: This is considered the most appropriate name
for the hill with respect to the information available to the author. Sometimes the name used does not correspond
to current Ordnance Survey map spelling and composition or the name may not appear
on any map. Where no appropriate name
has been discovered for the hill from any source, the Point (for example; Pt. 725m)
notation is used rather than making up a name that has no local or historical
evidence of use. The Welsh place-names
that appear in this list and that were sourced from Ordnance Survey mapping are
reproduced as simple compositions, with hyphenated and compound names reduced
to the component elements. It must be
noted that this process will on occasion result in loss of pronunciation
information and as such, is not ideal.
However, this protocol has been implemented in order to simplify the
composition due to the inappropriate and inconsistent hyphen use that Ordnance
Survey maps are prone to.
Summit
Height (m): This
gives the map height in metres of the hill above Ordnance Datum Newlyn (ODN),
often referred to as sea level. Where a
height is quoted to a decimal place it implies that the hill has been surveyed
by GPS / GNSS receiver (these heights may not match current Ordnance Survey map
heights). Where a ‘c’ (circa) appears
preceding the height it means there is no known spot height available and the
height has been estimated from contour interpolation.
1:50,000
Map: This column gives the number or numbers of
the 1:50,000 Ordnance Survey Landranger map that the summit of the hill appears
on.
1:25,000
Map: This column gives the number or numbers of
the 1:25,000 Ordnance Survey Explorer map that the summit of the hill appears
on.
Summit
Grid Reference: This is
the ten figure grid reference (10FGR) for the summit of the hill. This has either been produced by an accurate
survey, a map spot height or when neither is available by a centralised
position in an uppermost contour ring.
When the accurate survey has been conducted independent of the Ordnance
Survey a (S) for ‘survey’ will appear adjacent to the 10FGR, a (TP) if the
10FGR is taken to a ‘trig pillar’, a (B) if the 10FGR is taken to a ‘bolt’ or a
‘block’, a (L) if the 10FGR is taken to the position of a ‘levelled’ height on
old maps, a (HH) if the 10FGR is taken from a ‘hand-held’ GPS unit, a (SH) is
the 10FGR is taken to a ‘spot height’ either on current or old maps and an (I)
if the summit position has been ‘interpolated’ from contours.
Drop
(m): This column details the relative height of
the hill; this is commonly referred to as ‘drop’, ‘prominence’ or
‘reascent’. The drop is the height
difference between the summit and bwlch connecting the hill to next higher
ground along the watershed. The letter
‘c’ before the drop figure signifies there is no spot height or surveyed height
known for either summit or more usually, the bwlch, therefore a part of the
drop figure has been estimated from contour interpolation.
Bwlch
Grid Reference: This is
the ten figure grid reference (10FGR) for the bwlch of the hill. This has either been produced by an accurate
survey, a map spot height or when neither is available by a centralised
position between converging hill to hill and valley to valley contours. When the accurate survey has been conducted
independent of the Ordnance Survey a (S) for ‘survey’ will appear adjacent to
the 10FGR, a (L) if the 10FGR is taken to the position of a ‘levelled’ height
on old maps, a (HH) if the 10FGR is taken from a ‘hand-held’ GPS unit, a (SH)
is the 10FGR is taken to a ‘spot height’ either on current or old maps and an
(I) if the bwlch position has been ‘interpolated’ from contours.
Bwlch
Name / Feature: This is
the name that appears on the map for the bwlch or for a significant feature on
the area of the bwlch. If a name does
not appear on the map the initials ‘uom’ (unnamed on map) are used. As the use of drop as an intrinsic part of a
hill list is now well established it means that the bwlch is as important as
the summit in determining a drop value for the hill. Therefore it is only appropriate that the
name of the bwlch, or a significant feature on it appears in the list. This is the first known instance where the
bwlch name / feature is also included in the details within the hill list.
Bwlch
Height (m): This
gives the map height in metres of the bwlch above Ordnance Datum Newlyn (ODN),
often referred to as sea level. Where a
height is quoted to a decimal place it implies that the bwlch has been surveyed
by GPS / GNSS receiver (these heights may not match current Ordnance Survey map
heights). Where a ‘c’ (circa) appears
preceding the height it means there is no known spot height available and the
height has been estimated from contour interpolation.
Notes: This column gives details relevant to the
hill.
With special thanks to Geoff
Crowder and Aled Williams for past and present help and encouragement with the
listing of the Twmpau. Thanks are also
due to the people who submit 10 figure grid references to the Database of British and Irish Hills (DoBIH) and for DoBIH making these available for public
use.
To access the Twmpau – 700m P30 list please click {here}
Llyn y Dywarchen is immediately below two of Wales' P30s |
Next instalment of the Twmpau due on 15th May 2015
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