Pt. 416.8m (SH 837 332) – 400m Sub-Pedwar addition
There has been an addition to the listing of Y Pedwarau due to analysis of LIDAR data
by Aled Williams. Y Pedwarau is the title for the list of 400m hills of Wales and
takes in all Welsh hills at or above 400m and below 500m in height that have a
minimum 30m of drop, the list is a joint compilation between Myrddyn Phillips
and Aled Williams, and it commenced publication on Mapping Mountains on the
30.01.17.
Accompanying the main Y
Pedwarau list are five categories of sub hills, with this addition
affecting the 400m Sub-Pedwar
category. The criteria for 400m Sub-Pedwar qualification is all
Welsh hills at or above 400m and below 500m in height with 20m or more and
below 30m of drop.
Prior to analysis of LIDAR data the hill was categorised
with 19m of drop based on the 417m summit spot height that appears on the
Ordnance Survey 1:25,000 Explorer map and the 398m bwlch spot height that
appears on the Ordnance Survey enlarged mapping hosted on the Geograph website.
The hill is situated in the Arenig group of hills with its Cardinal Hill being Arenig Fawr (SH 827 369) and is placed
in the Region of North Wales (Region A, Sub-Region A3), and is positioned with
the small community of Llanuwchllyn
to its south-east.
If wanting to visit the hill permission to do so
should be sought as it is not on open access land and to add to access problems
the map indicates that its summit is immersed in conifer trees. However, it is positioned between two public
footpaths with the one to its west nearest to its summit.
The hill is being listed by the point (Pt. 416.8m)
notation as the authors do not know a suitable name for it either from historical
research or local enquiry and its addition to 400m Sub-Pedwar status is due to the analysis of LIDAR data by Aled
Williams. LIDAR (Light Detection & Ranging) is
highly accurate height data that is now freely available for much of England
and Wales.
Aled’s analysis of LIDAR data gives the hill the
following details:
Pt.
416.8m
Summit
Height: 416.8m (converted to OSGM15)
Summit
Grid Reference: SH 83743 33235
Bwlch
Height: 396.7m (converted to OSGM15)
Bwlch
Grid Reference: SH 83569 33326
Drop: 20.1m
Therefore, the 416.8m (converted to OSGM15) LIDAR
data produced for the summit position at SH 83743 33235 and the 396.7m (converted to OSGM15) LIDAR data
produced for the bwlch position at SH 83569 33326 gives
this hill 20.1m of drop which is sufficient for its inclusion as a 400m Sub-Pedwar.
The full details for the hill are:
Cardinal Hill: Arenig
Fawr
Summit Height: 416.8m (converted
to OSGM15) (LIDAR data)
Name: Pt. 416.8m
OS 1:50,000 map: 124, 125
Summit Grid Reference: SH 83743 33235
Drop: 20.1m (converted
to OSGM15) (LIDAR data)
The overall total for Y
Pedwarau remains at 445 hills with eight additions, and ten
reclassifications to 400m Sub-Pedwar
status since publication of the list by Europeaklist in May 2013.
The overall total for the 400m
Sub-Pedwarau is now 217 with 19 hills being added and 15 hills being taken
out of this category since publication of the list by Europeaklist in May 2013.
The list of Pedwar
hills is available from the Haroldstreet website (January 2014) with all
subsequent changes detailed on the Mapping Mountains site, with the list also
having commenced publication on Mapping Mountains on the 30.01.17.
For the additions, reclassifications and deletions to Y Pedwarau reported on Mapping Mountains
since the May 2013 publication of the list by Europeaklist please consult the
following Change Registers:
Myrddyn Phillips and Aled Williams (May 2017)
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