Moel Fron Goch (SJ 008 208)
There has been a Significant Height Revision to a hill that is listed in the Y Trichant – The 300m Hills of Wales, with the summit height, bwlch height and their locations, the drop and status of the hill derived from LIDAR analysis conducted by Myrddyn Phillips.
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| LIDAR image of Moel Fron Goch (SJ 008 208) |
The criteria for the list that this height revision applies
to are:
Y Trichant
– The 300m Hills of Wales – Welsh
hills at or above 300m and below 400m in height that have 30m minimum drop, with an accompanying sub list entitled the
Sub-Trichant, with the criteria for this sub category being all Welsh hills at
or above 300m and below 400m in height with 20m or more and below 30m of
drop. The list is authored by Myrddyn Phillips with the
Introduction to the list and the renaming of it appearing on Mapping Mountains
on the 13th May 2017, and the Introduction to the Mapping Mountains
publication of the list appearing on the 1st January 2022.
 |
| Y Trichant - The 300m Hills of Wales by Myrddyn Phillips |
The name the hill is listed by is Moel Fron Goch, and it is adjoined to the Foel Cedig group of hills, which are situated in the southern part of North
Wales (Region A, Sub-Region A3), and
it is positioned with a minor road to its north-east, and the B4393 road and
Llyn Efyrnwy (Lake Vyrnwy) to its south, and has the village of Llanwddyn
towards the south-east.
When the original 300m height band of Welsh P30 hills were published on Geoff Crowder’s v-g.me website, this hill was not
included in the Hills to be surveyed
sub list, as it was considered not to meet the criteria then used for this sub
category.
After the sub list was standardised, and
interpolated heights and drop values also included the details for this hill
were re-evaluated and it was listed with 22m of drop, based on the 333m summit
spot height that appears on the Ordnance Survey 1:25,000 Explorer map and the 311m
bwlch spot height that appeared on the Ordnance Survey Vector Map Local hosted
on the Geograph website and which was entitled the Interactive Coverage Map.
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| 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.
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| LIDAR summit image of Moel Fron Goch (SJ 008 208) |
LIDAR analysis gives the summit height of this
hill as 336.9m and this comes within the parameters of the Significant Height
Revisions used within this page heading, these parameters are:
The term Significant Height Revisions applies to
any listed hill whose interpolated summit height and Ordnance Survey or Harvey
map summit spot height, has a 2m or more discrepancy when compared to the
survey result produced by the Trimble GeoXH 6000 or analysis of data produced
via LIDAR. Also included are hills whose
summit map data is missing an uppermost ring contour when compared to the data
produced by the Trimble or by LIDAR analysis.
Therefore, the new listed summit height of this
hill is 336.9m and this was derived from LIDAR analysis, this is 3.9m higher than
the previously listed summit height of 333m which appears as a spot height on
the Ordnance Survey 1:25,000 Explorer map.
The full details for the hill are:
Group: Foel Cedig
Name: Moel Fron Goch
OS 1:50,000 map: 125
Summit Height (New Height): 336.9m (LIDAR)
Summit Grid Reference: SJ 00828 20877 (LIDAR)
Bwlch Height: 310.9m (LIDAR)
Bwlch Grid Reference: SJ 00834 21134 (LIDAR)
Drop: 26.0m (LIDAR)
Myrddyn Phillips (May
2022)
