Panylau Gwynion (SH 935
063)
There has been a Summit Relocation to a hill that
is listed in the Y Pedwarau – The 400m
Hills of Wales, with the summit height, bwlch height and their locations,
the drop and status of the hill derived from detail on contemporary maps
produced from Ordnance Survey data and a Trimble GeoXH 6000 survey conducted by
Myrddyn Phillips and Aled Williams.
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Panylau Gwynion (SH 935 063) |
The criteria for the list that this summit
relocation applies to are:
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Y Pedwarau - The 400m Hills of Wales by Myrddyn Phillips and Aled Williams |
The name the hill is listed by is Panylau Gwynion
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 the A470 road to its south-west and a minor road to its
south-east, and has the village of Talerddig towards the south.
When the 1st edition of the Y Pedwarau was published by Europeaklist in May 2013, this hill was
listed with 39m of drop, based on the 451m summit spot height that appears on
the Ordnance Survey 1:25,000 Explorer map at SH 93575 06311 and a 412m bwlch
spot height that appeared on the Ordnance Survey Vector Map Local that was
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 |
The upper part of this hill has two 450m map ring
contours. The 451m map spot height
appears in a relatively large 450m contour that until recent times was a part
of a conifer plantation, whilst just to the west of the plantation’s boundary
fence was a small 450m map ring contour on open ground that logs on the Hill
Bagging website reported as a knoll and which could be higher.
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The Trimble GeoXH 6000 gathering data from the lower deforested top with the higher summit of Panylau Gwynion in the background |
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The Trimble GeoXH 6000 gathering data at the heathery knoll summit of Panylau Gwynion with the lower deforested top in the background |
However, it was not until the Trimble GeoXH 6000
survey that the details for this hill could be accurately re-assessed. The summit height and position produced by
the Trimble GeoXH 6000 survey is 450.3m positioned at SH 93557 06357, as
opposed to 449.1m positioned at SH 93575 06303 to the high point of what used
to be within the conifer plantation, and this position in relation to that
previously given 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, 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 judged to be a relatively recent man-made construct, 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 the
Trimble GeoXH 6000 survey is 450.3m and this is positioned at SH 93557 06357,
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 55
metres south south-eastward from where the previously listed summit is
positioned.
ills of Wales, and are reproduced below@
The full details for the hill are:
Group: Carnedd Wen
Name: Panylau Gwynion
OS 1:50,000 map: 125
Summit Height: 450.3m
(converted to OSGM15, Trimble GeoXH 6000)
Summit Grid Reference (New Position): SH 93557 06357 (Trimble GeoXH 6000)
Bwlch Height: 412m (spot
height)
Bwlch Grid Reference:
SH 93627 06715 (spot height)
Drop: 38m (Trimble
GeoXH 6000 summit and spot height bwlch)
Myrddyn Phillips and Aled Williams (September 2022)
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