Foel Cedig (SH 981 283)
There has been a Summit Relocation to a hill that is listed in the Y Pellennig – The Remotest Hills of Wales, The Welsh Highlands – Uchafion Cymru and the 600m Twmpau, with the summit height, bwlch height and their locations, the drop and status of the hill derived from a Trimble GeoXH 6000 survey conducted by Myrddyn Phillips with the bwlch surveyed on the 19th October 2016 and the summit on the 16th August 2018.
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| Foel Cedig (SH 981 283) on the left and Cyrniau Nod (SH 988 279) on the right |
The criteria for the three listings that this
summit relocation applies to are:
Y Pellennig –The Remotest Hills of Wales - Welsh hills whose summit is at least 2.5km from the nearest paved public road and the hill has a minimum 15m of drop. The list is co-authored by Myrddyn Phillips and Aled Williams and is available as a downloadable e-booklet or print-booklet version on Mapping Mountains Publications with the up-to-date master list available on Mapping Mountains to download in Google Doc format.
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| Y Pellennig - The Remotest Hills of Wales by Myrddyn Phillips and Aled Williams |
The Welsh Highlands – Uchafion Cymru – Welsh hills at or above 500m in height with 15m minimum drop, with an accompanying sub list entitled the Welsh Highland Subs, the criteria for which is all Welsh hills at or above 500m in height with 10m or more and below 15m of drop. This list is authored by Myrddyn Phillips and Aled Williams with the Introduction to the list published on Mapping Mountains in November 2015 and the latest update relating to the list published on Mapping Mountains in January 2023.
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| The Welsh Highlands - Uchafion Cymru by Aled Williams and Myrddyn Phillips |
600m Twmpau - Welsh hills at or above 600m and below 700m in height with 30m minimum drop, with an accompanying sub list entitled the 600m Sub-Twmpau with the criteria for this sub category being all Welsh hills at or above 600m and below 700m in height with 20m or more and below 30m of drop, with the word Twmpau being an acronym standing for thirty welsh metre prominences and upward. The list is authored by Myrddyn Phillips and is available to download in Google Doc format from Mapping Mountains.
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| 600m Twmpau by Myrddyn Phillips |
The name the hill is listed by is Foel Cedig, and it is the highest point in its group of hills, which are wyn range of hills, which are situated in the
south-eastern part of North Wales (Region C1, Sub-Region C1B), and it is positioned
to the north of Llyn Efyrnwy (Lake Vyrnwy) and has the town of Y Bala towards
the north-west.
When these lists were first compiled the qualifying summit was listed as Cyrniau Nod with a 667m summit height positioned at SH 988 279, based on the spot height that appears on the Ordnance Survey 1:50,000
Landranger and 1:25,000 Explorer map.
Whilst the summit of Foel Cedig which is positioned at SH 981 283 is
given a 666m spot height on these maps.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
As the surveying technique that produced these two spot heights has a +/- 3m margin of
uncertainty applied to it, it meant that Foel Cedig could in fact be higher
than Cyrniau Nod, therefore both hills were surveyed with the Trimble GeoXH
6000.
The results from these two surveys are given
below:
Foel Cedig:
667.417m at SH 98170 28327
Cyrniau Nod:
666.207m at SH 98847 27920
Since the qualifying summit has been relocated to
Foel Cedig this has also affected the lists of Marilyns, Humps, Simms, Hewitts,
Nuttalls and Tumps, with Alan Dawson as list author of the Marilyns, Simms and
Hewitts having accepted this result the other list authors soon followed suit.
A subsequent Leica GS15 survey conducted by John
Barnard and Graham Jackson on the 15th September 2018 resulted in
the following:
Foel Cedig:
667.479m at SH 98170 28327
Cyrniau Nod:
666.234m at SH 98847 27918
The summit of Foel Cedig was also subsequently surveyed by Alan Dawson on the 25th November 2018 using a Leica RX1250:
Foel Cedig: 667.503m at SH 98170 28327
Data sets of ten and eleven minutes were collected
with the Trimble GeoXH 6000, whilst 122 and 121 minute data sets were collected
with the Leica GS15 and 24 minutes with the Leica RX1250.
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| The Trimble GeoXH 6000 gathering data at the summit of Foel Cedig with Cyrniau Nod in the background |
The 667.4m summit height produced by the Trimble
GeoXH 6000 survey and its position in relation to that of Cyrniau Nod 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.
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| The Trimble GeoXH 6000 gathering data at the summit of Cyrniau Nod with Foel Cedig in the background on the left |
Therefore, the new listed summit height of this hill is 667.4m and is positioned at SH 98170 28327, and this was derived from a Trimble GeoXH 6000 survey. This position is approximately 800 metres north-westward from where the old listed summit of Cyrniau Nod is positioned.
The full details for the hill are:
Group: Foel Cedig
Name: Foel Cedig
OS 1:50,000 map: 125
Summit Height: 667.4m
(converted to OSGM15)
Summit Grid Reference (New Position): SH 98170 28327
Bwlch Height: 487.4m (converted
to OSGM15)
Bwlch Grid Reference:
SH 94458 27324
Drop: 180.0m
Remoteness: 3.200 km
Myrddyn Phillips and Aled Williams (January 2019)
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