16.08.18 Pen y Cerrig Duon (SH 953 281), Pen y Boncyn
Trefeilw (SH 962 283), Stac Rhos (SH 969 279), Cefn Gwyntog (SH 975 266), Foel
Cedig (SH 981 283) and Cyrniau Nod (SH 988 279)
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| Stac Rhos (SH 969 279) on the left and Pen y Boncyn Trefeilw (SH 962 283) on the right |
The heather moor of Y
Berwyn can be a wild place to visit; it incorporates a great swathe of land from the north and the Afon Dyfrdwy (River Dee) as it passes the confines of
Corwen and Llangollen all the way south to the outskirts of Dinas Mawddwy.
I’d visited many times
before, and for me it is at its best when rain clouds quickly skirt over the
land giving flashes of light interspersed with deep grey cloud and when the
purple of the heather is in bloom, adding delicate colour to an otherwise bleak
scene. Today was one of those days, with
conditions to savour.
The hills planned for
today comprise those to the immediate east of the upper Cwm Hirnant, from Pen y
Cerrig Duon to Cyrniau Nod, in all I wanted to survey a minimum of 14 points,
and knew that these surveys would take me in to bylchau I had not visited
before, some no doubt being wild and inhospitable places.
I was walking up the
track toward these hills from the top of the minor road as it crests its way
from Llyn Efyrnwy (Lake Vyrnwy) toward Llyn Tegig and Y Bala by 7.45am. The sky was menacing with deep grey cloud and
rain showers further west, and yet thankfully the near hills were clear of murk
and clag.
The first hill on my
agenda was Pen y Cerrig Duon which I had surveyed using my basic levelling
method in July 1998, the track led around its northern periphery and from its
high point I made my way up through heather and rough grass to its summit. As the Trimble gathered its allotted data I
stood back and looked out on darkening cloud to the west and north as rain
scattered all around, and yet except for a few breeze blown drops I remained
dry.
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| Gathering data at the summit of Pen y Cerrig Duon |
I quickly re-joined the
track which although an obvious distraction to this land as it snakes its
gravelled way around these hills, it is nonetheless a god send for any hill
walker, as otherwise these hills would be far rougher and much more difficult
to visit. The track brought me down to
the connecting bwlch, I spent a number of minutes assessing the lay of land and
eventually chose a spot beside a small stagnant pool for Trimble placement. From this position I was looking out toward a
mass of dark shower cloud as it deposited its wet stuff further north, I hoped
it would quickly push away.
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| Gathering data at the bwlch of Pen y Cerrig Duon |
I’ve talked with local farmers
who were working this land before the track was bulldozed and with the farmer
who first put it in, their life must have been hard before, as access would not
have been easy, and the convenience of the track now led me up toward the
summit of the next hill; Pen y Boncyn Trefeilw.
The summit area of this
hill, along with my next; Stac Rhos, have greened grazing slopes that are at
contrast with the heather moor, they have been reclaimed in years gone past and
now shine emerald against their heather counterparts.
I wanted to take two
data sets from the summit of Pen y Boncyn Trefeilw, one on a peat hag that
looks unusually out of place as its high point forever disappears, and the
other a little further north where outside of the peat hag the high point of the
hill is placed, both are similar in height and I hoped the Trimble would be
able to separate them.
As I stood on the top of
the peat hag the uppermost part flopped about almost in mid-air and it will not
be long before this as its sides before, is eroded and gives way to the
elements. I positioned one of a number
of rocks constituting a makeshift cairn on its high point and positioned the
Trimble on this to give it a semblance of elevation above its immediate surrounds,
then measured the offset between its internal antenna and the ground below and
proceeded to take another data set. The
Trimble was then set up on the high ground to the north-east of the peat hag
and a further five minute data set gathered and stored.
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| Gathering data at the first position for the summit of Pen y Boncyn Trefeilw |
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| Gathering data at the second position for the summit of Pen y Boncyn Trefeilw |
I was now at the mercy
of the heather as the next survey consisted of two data sets, this is where the
two 605m spot heights appear on the Ordnance Survey Interactive Coverage Map
hosted on the Geograph website, and I wanted to investigate each, assess the
land near to these positions and gather further data.
I hadn’t immersed myself
in the delights of this bwlch before, having always circumvented it on the track
to its north. It was a soft undulating
place to visit, with each step sinking in to copious amounts of heather and
peat channels leading this way and that.
Approaching from above gave me a chance to look down on this land and
even from afar it was obvious that there are two main points where its critical
point may lie, and this matched the information on the Ordnance Survey map.
Having arrived at the
first position I quickly set the Trimble up and tried to find a semblance of
dry ground to stand on as it gathered its allotted data, it felt good to be on
ground I had not visited and this for me is one of the advantages of operating the
Trimble and surveying these places.
The second point to
survey was again in a peat channel and once at the position where the valley to
valley traverse met I assembled the Trimbe and stood back luxuriating in the
early morning warmth that was now breaking through the ongoing breeze of the
day.
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| Gathering data at the second position for the bwlch of Stac Rhos |
Leaving the heathery
confines of the bwlch I headed back to the comfort and perceived safety of the
track which gave access to the next high grazing field which led toward the
summit of Stac Rhos. The high point of
seven 630m contour rings is the first one on the right as the fence from the
track is followed up the hill; it is marked with a small cairn.
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| Gathering data at the summit of Stac Rhos |
Once Trimble data were
gathered and stored I headed in to the true wilderness of these hills, away
from the track in to the heather and wild grasslands of the Y Berwyn. Another data set was gathered at the next
bwlch and I then headed up toward a fence, the underfoot conditions were
surprisingly easy considering it was pathless.
There is now a path beside this fence and this continues to join one
that heads toward the summit of Cefn Gwyntog, this is a hill that is a there
and back from the ease of the track and used to involve a large amount of
heather bashing, the path now eases progress, but the hill still feels disconnected
from its neighbours, it is an outlier and by far the better for it.
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| Gathering data at the critical bwlch of Pen y Boncyn Trefeilw |
On my way to the high
point of Cefn Gwyntog I wanted to survey its critical bwlch and considering the
acres of heather comprising the hill this was remarkably easy to find. Once data were gathered and stored I pressed
on toward the hill’s summit.
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| Gathering data at the critical bwlch of Cefn Gwyntog |
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| The darkened profile of Foel Cedig |
I had three data sets planned
to take at the summit area of Cefn Gwyntog, one from where LIDAR places the
high point and a further two from land beside or close to the two cairns that
have been put in place signifying where people think the high point is
positioned. I remember coming this way
many years ago and finding a motorcycle helmet on top of one of these cairns,
which made me smile, this has long since gone.
The LIDAR summit of Cefn
Gwyntog is 2-3 metres from the narrow path and consists of rough grass, I set
the Trimble up and decided that I would take ten minute data sets from each of
these three points, as the equipment gathered its all-important data I stood
back in the increasing westerly breeze as it flew across the hill and watched a
mass of deepening slate grey rain cloud gather over the Aran which quickly pushed
eastward.
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| Gathering data at the summit of Cefn Gwyntog |
The second point I
wanted to survey is where an Abney level survey places ground of equal height and
where LIDAR distinguishes another high point, but which it also distinguishes
as lower than the ground from where my fist data set was taken. This second point is situated 13 metres from
the larger of the two cairns, and again as the Trimble gathered data I looked
at the mass of rain cloud as it crept up the valley to my south, this area was
getting decidedly wet.
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| Gathering data during the second survey on the summit area of Cefn Gwyntog |
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| Gathering data during the second survey on the summit area of Cefn Gwyntog |
The third survey was
from beside the smaller of the two cairns and is where the prioritised summit
is currently given, by now the dark grey cloud was swamping the valley to my
immediate south and yet all I felt were a few breeze blown drops of rain, I had
been fortunate and once the third summit survey was complete I packed the
Trimble away and retraced my way back on the narrow path and down to the
connecting bwlch and then up toward a forlorn looking wooden gate which gives
access toward the easy going on the track.
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| Gathering data during the third survey on the summit area of Cefn Gwyntog |
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| The narrow path and gate leading toward Cefn Gwyntog |
It felt good to be back
on the track, and this feeling is one that I have experienced on these hills
many times before, there is a comfort to easy ground however much one
appreciates the wilder landscape.
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| The track on the moor leading toward Foel Cedig |
There were three surveys
remaining and I hoped these would distinguish which point is higher, the first being
the summit of Foel Cedig which is given as 666m spot height on contemporary
Ordnance Survey maps, the third survey is the summit of Cyrniau Nod which is
given a 667m summit spot height and the second survey was to a 665m contour
ring (OS Maps) that is positioned between the two.
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| Arenig Fawr from Foel Cedig |
By now the southerly
murk had bi-passed these hills and intermittent warmth as the sun broke free of
layers of cloud gave a welcoming aspect to the remainder of the walk. The summit of Foel Cedig is placed relatively
near the high point of the track and was only a short walk to its small and
attractive knoll with has rock exposed on its upper western fringes. I placed my rucksack on its summit and
positioned the Trimble with its internal antenna aligned with its high point
and waited in the sun and strong breeze for ten minutes of data to be gathered
and stored.
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| Gathering data at the summit of Foel Cedig |
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| The Trimble set-up position at the summit of Foel Cedig |
After re-joining the
track I headed back in to the heathery surrounds of the adjacent 665m ring
contour and waded through seldom visited grass on its high point before
determining which tussocky bulge to position the Trimble beside, and another
ten minute data set was taken.
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| Gathering data at the 665m (OS Maps) contour ring between Foel Cedig and Cyrniau Nod |
Just one survey remained
and that was the summit of Cyrniau Nod, supposedly the highest of all of these
hills. Its summit is positioned toward
the end of its high ridge that heads southward in to a morass of heather and
bog, and close to its highest point a cairn with an old post signifies journeys
end, well, journeys end before either the next hill or a long walk back on the
track.
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| Gathering data at the summit of Cyrniau Nod |
I’d previously surveyed
this hill with John Barnard for summit position and the designated spot soon
had a Trimble on it perched atop my rucksack gathering data.
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| Photo taken during the survey for the summit position of Cyrniau Nod |
During the last hour I’d
heard gun shots and spotted a number of vehicles on the track and a party of
five or six people walk in a line across the moor heading in the direction of
Cefn Gwyntog, and as I retraced my inward route back on the track I soon came
across the gamekeeper of these moors, we stopped and talked and he told me that
he came from the Wrexham area and has been in his current job for a year or so. I then continued down to where the shooting
party were sitting beside the track.
They had flushed upwards of 40 grouse from the heather and shot
two. I chatted, took photographs, and asked
their permission to put a selection on my blog and waved my goodbyes.
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| Some of the shooting party |
I re-visited the summits
of Stac Rhos and Pen y Boncyn Trefeilw on my way back, on each I sat and looked
and considered the state of play with things, including that in the hill
bagging world.
As I re-joined the track
dark clouds again massed over the Aran as the slow rumble of a Hercules plane
passed overhead.
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| The way home |
These hills will forever
bring me back to them, they are not the most dramatic but on a day such as
today when the showers sped across their wild land and the breeze blew they
give welcoming solace with peaceful surrounds to gather ones thoughts.
Survey Result:
Pen y Cerrig Duon
Summit Height: 610.1m (converted to OSGM15)
Summit Grid Reference: SH 95302 28118
Bwlch Height: 598.8m (converted to OSGM15)
Bwlch Grid Reference: SH 95452 28086
Drop: 11.3m
Dominance: 1.85%
Pen y Boncyn Trefeilw
Summit Grid Reference: SH 96250 28329 (Trimble GeoXH 6000) SH 96250 28328) (Leica RX1250)
Bwlch Height: 588.4m (converted to OSGM15)
Bwlch Grid Reference: SH 97406 27854
Drop: 55.6m (Trimble GeoXH 6000) 55.8m (Leica RX1250 summit and Trimble GeoXH 6000 bwlch)
Dominance: 8.63% (Trimble GeoXH 6000) 8.67% (Leica RX1250 summit and Trimble GeoXH bwlch)
Stac Rhos
Summit Height: 629.4m (converted to OSGM15, Trimble GeoXH 6000) 629.8m (converted to OSGM15, Leica RX1250)
Summit Grid Reference: SH 96915 27925 (Trimble GeoXH 6000) SH 96916 27925 (Leica RX1250)
Bwlch Height: 603.3m (converted to OSGM15)
Bwlch Grid Reference: SH 96519 28125
Drop: 26.1m (Trimble GeoXH 6000) 26.6m (Leica RX1250 summit and Trimble GeoXH 6000 bwlch)
Dominance: 4.15% (Trimble GeoXH 6000) 4.22% (Leica RX1250 summit and Trimble GeoXH 6000 bwlch)
Cefn Gwyntog
Summit Height: 613.8m (converted to OSGM15)
Bwlch Height: 587.1m (converted to OSGM15)
Bwlch Grid Reference: SH 97493 27338
Drop: 26.7m
Dominance: 4.35%
Foel Cedig
Summit Height: 667.4m (converted to OSGM15) (confirmed as
higher than Cyrniau Nod [SH 98847 27920])
Bwlch Height: 487.4m (converted to OSGM15, previously
Trimbled)
Bwlch Grid Reference: SH 94458 27324
Drop: 180.0m
Dominance: 26.97%
Cyrniau Nod
Summit Height: 666.2m (converted to OSGM15, Trimble GeoXH 6000) 666.2m (converted to OSGM15, Leica GS15) (confirmed as
lower than Foel Cedig [SH 98170 28327])
Summit Grid Reference: SH 98847 27920 (Trimble GeoXH 6000) SH 98847 27918 (Leica GS15) (summit relocation)
Bwlch Height: 656.2m (Trimble adjusted LIDAR)
Bwlch Grid Reference: SH 98524 28394 (LIDAR)
Drop: 10.0m (Leica GS15 summit and LIDAR bwlch)
Dominance: 1.50% (Leica GS15 summit and Trimble adjusted LIDAR bwlch)
