Cae Duon (SJ 075 090)
There has been a Summit Relocation to a hill that is listed in the The Welsh P15s, with the summit height, bwlch height and their locations, the drop and status of the hill derived from LIDAR analysis conducted by Myrddyn Phillips.
%20-%20LIDAR%20hill%202.jpg) |
| LIDAR image of Cae Duon (SJ 075 090) |
The criteria for the list that this summit relocation applies
to are:
The Welsh
P15s – Welsh hills with 15m
minimum drop, irrespective of their height, with an accompanying sub list entitled the Welsh Sub-P15s,
with the criteria for this sub category being all Welsh hills with 14m or more
and below 15m of drop. The list is authored by Myrddyn Phillips, with the
Introduction to the list appearing on Mapping Mountains on the 10th
May 2019.
 |
| The Welsh P15s by Myrddyn Phillips |
The name the hill is now listed by is Cae Duon,
and this was derived from the Tithe map, and it is adjoined to the Carnedd Wen group
of hills, which are situated in the southern
part of North Wales (Region A, Sub-Region A3), and it is positioned with minor roads to its
north-west and east, with the A458 road to its south-west, and has the town of
Llanfair Caereinion towards the south-east.
When the listing that became known as The Welsh P15s was being compiled, this
hill was included in the main list with an estimated c 15m of drop, based on
the 168m summit spot height positioned on a road at SJ 07581 09015 that appears
on the Ordnance Survey 1:25,000 Explorer map, and an estimated c 153m bwlch
height, based on interpolation of 5m contouring between 150m – 155m.
%20-%201%2025000.jpg) |
| Extract from the Ordnance Survey 1:25,000 Explorer map |
However, it was not until LIDAR became available
that the details for this hill could be accurately re-assessed. The LIDAR (Light Detection & Ranging)
technique produced highly accurate height data that is now freely available for
much of England and Wales.
LIDAR analysis gives the highest ground on this
hill as 167.8m positioned at SJ 07595 09031.
However, this is to the top of a man-made mound and protocols dictate
that as this is deemed a relatively recent man-made construct such ground is
discounted from the height of a hill.
%20-%20LIDAR%20summit%203.jpg) |
| LIDAR summit image of Cae Duon (SJ 075 090) |
The height produced by LIDAR analysis to the
natural summit of this hill is 167.2m and is positioned at SJ 07592 09025, and this comes within the parameters of the
Summit Relocations used within this page heading, these parameters are:
The term Summit Relocations applies when the high
point of the hill is found to be positioned; in a different field, to a
different feature such as in a conifer plantation, within a different map contour either on Ordnance
Survey maps or interactive mapping, to a different point where a number of
potential summit positions are within close proximity, when natural ground or
the natural and intact summit of a hill is confirmed compared to a higher point
such as a raised field boundary or covered reservoir that is considered a
relatively recent man-made construct, or the de-twinning of a summit, or a
relocation of approximately 100 metres or more in distance from either the
position of a map spot height or from where the summit of the hill was
previously thought to exist.
Therefore, the summit
height produced by LIDAR analysis is 167.2m and
is positioned at SJ
07592 09025, this position is not given a spot height on the contemporary
Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map, and is
approximately 11 metres north-eastward from where the spot height appears on
the road and approximately 6 metres south-westward from the high point of the
man-made mound.
The full details for the hill are:
Group: Carnedd Wen
Name: Cae Duon
OS 1:50,000 map: 125
Summit Height: 167.2m (LIDAR)
Summit Grid Reference (New Position): SJ 07592 09025 (LIDAR)
Bwlch Height: 150.9m (LIDAR)
Bwlch Grid Reference: SJ 07395 09423 (LIDAR)
Drop: 16.25m (LIDAR)
Myrddyn Phillips (May
2025)
No comments:
Post a Comment