Mynydd Cribau (SN 759 552)
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%201.jpg) |
| LIDAR image of Mynydd Cribau (SH 759 552) |
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 listed by is Mynydd Cribau, and
it is adjoined to the Moel Siabod group of hills, which are situated in the north-western part of North Wales (Region A,
Sub-Region A1), and it is positioned with the
A5 road to its north and east, and the A470 road to its south, and has the village
of Betws-y-coed towards the east north-east.
When the listing that became known as The Welsh P15s was being compiled, this
hill was included in the accompanying P14 sub list with an estimated c 14m of
drop, based on the 322m summit spot height positioned at SH 75790 55014 that
appeared on the Ordnance Survey Vector Map Local hosted on the Geograph website
and which was entitled the Interactive Coverage Map and an estimated c 308m
bwlch height, based on interpolation of 10m contouring between 300m – 310m.
%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.
%20-%20LIDAR%20summit%201.jpg) |
| LIDAR summit image of Mynydd Cribau (SH 759 552) |
The height produced by LIDAR analysis to the
summit of this hill is 322.0m and is positioned at SH 75985 55229, whilst
LIDAR gives the highest ground adjacent to where the 322m spot height appeared as
320.9m positioned at SH 75788 55018, 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 listing of a new twin
summit or 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 322.0m and this is positioned at SH 75985 55229. 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 210 metres north-eastward
from where
the highest ground adjacent to the 322m spot height appeared on the Ordnance Survey Vector Map Local hosted on the
Geograph website and which was entitled the Interactive Coverage Map.
The full details for the hill are:
Group: Moel Siabod
Name: Mynydd Cribau
OS 1:50,000 map: 115
Summit Height: 322.0m (LIDAR)
Summit Grid Reference (New Position): SH 75985 55229 (LIDAR)
Bwlch Height: 308.0m (LIDAR)
Bwlch Grid Reference: SH 76100 55557 (LIDAR)
Drop: 14.05m (LIDAR)
Myrddyn Phillips (August
2026)
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