The Welsh P15s
All
Welsh hills with 15m minimum prominence
Introduction to the Mapping Mountains List
In early May
2019 the compilation of The Welsh P15s was finally completed. This list took over 8 years to
compile, with approximately a year dedicated to the hills at or above 500m in
height and the remaining hills below 500m being compiled from 2012 onwards.
The criterion for The Welsh
P15s is all Welsh hills that have 15m minimum drop, irrespective of their
height. With an accompanying sub list
taking in all Welsh hills that have 14m or more and below 15m of drop.
The list was introduced via
articles published on Mapping Mountains on the 10th May 2019 and on
the UKHillwalking website.
At the time of completion The
Welsh P15s comprised:
5,431 P15 hills with 435 P14
subs.
As with many listings of hills,
the contents therein can be used to create sub sets of hills, and the further
down the scale of either height and/or drop one goes, the more sub sets of
lists can be created. The Welsh P15s is no
different with some of the lower prominence hills being extracted and
prioritised for other lists.
It is always my intention when
listing hills to include sufficient detail to give merit to each hill’s
inclusion. This can be time consuming,
especially for numerical data where GNSS receivers and LIDAR analysis are now
available giving accurate height, and also for hill name data when each is
researched using a variety of sources including local enquiry, Ordnance Survey
maps; both contemporary and historical and the Tithe maps; with the latter
especially important for lower heighted hills.
Therefore, listing The Welsh
P15s in Google Doc format via an excel spreadsheet will be a time consuming
process. The prioritised lower
prominence hills extracted from The Welsh P15s for other hill lists mainly
relate to the height bands at and above 400m.
Therefore, the groupings of hills that will appear in the foreseeable
future on Mapping Mountains will in the main be for those whose highest hill is
below 400m in height.
As the research required for
each hill is time consuming future groupings of hills for this list will only
appear when complete, and the first Group where place name and numerical data for
each hill has been completed is for Ynys Môn and
its adjacent islands; with the highest hill being Mynydd Twr.
At the time of publication the Ynys
Môn and adjacent islands Group comprise 172
P15s and 26 P14 subs, with a further eight hills listed that have been deleted
from the original compilation of this list.
Further Groups will appear on
Mapping Mountains when fully researched and complete. These will appear on an ad-hoc basis with no
regimented time scale for publication.
Access: The Welsh P15s is a
catalogue of all hills in Wales that have 15m minimum drop (14m minimum drop
including the sub list). If wanting to
visit any of these hills please abide by any legal restrictions and if unsure
of permissible access ask permission to visit from the respective landowner.
Risks: Many of the
hills listed in The Welsh P15s are relatively easy to visit, but hill walking
is an activity that can bring many risks and dangers, both natural and
man-made. You should not climb hills
beyond your capabilities, and should fully appraise yourself of, and prepare
for, the possible risks before attempting to scale any hill. Climbing, hill and mountain walking and
mountaineering are activities with a danger of personal injury or death. Participants in these activities should be
aware of and accept these risks, and be responsible for their own actions and
involvement.
The Mapping Mountains list
consists of the following:
Name: This is considered the most appropriate name
for the hill, based on local usage where this is known. Names have been researched from a variety of
sources including; local enquiry, contemporary and historical Ordnance Survey
maps and for many of the lower heighted hills from the Tithe map. The name used does not always correspond to
contemporary Ordnance Survey map spelling and/or composition or the name may
not appear on any map. Where an
appropriate name is not forthcoming for the hill, the Point (for example; Pt.
66.8m) notation is used rather than making up a name that has no local or
historical evidence of use.
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 GNSS receiver (survey grade GPS)
or obtained from LIDAR analysis (these heights may not match current Ordnance
Survey map heights), with the heights produced by GNSS receiver converted to
OSGM15. 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 for the summit of the hill. This has either been produced by an accurate
survey via GNSS receiver or LIDAR, a map spot height, hand-held GPS via DoBIH
or for interpolated heights by a centralised position in an uppermost contour
ring.
Summit
Grid Reference extracted from: Details of where the ten figure grid
reference for the summit was derived.
Drop (m): This
column details the prominence of the hill, otherwise known as drop or
re-ascent. The drop is the height
difference between the summit and the lowest connecting bwlch to the higher
parent peak 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.
Notes: This column gives additional information
relating to the hill.
Thanks are given 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.
Mapping Mountains downloadable list in Google Doc format
The Ynys Môn and adjacent islands Group has also been published on Haroldstreet:
Ynys Môn and adjacent islands – P15s
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