17.09.17
Moel Siabod (SH 705 546, only bwlch surveyed), Clogwyn Bwlch y Maen (SH 679 542),
Carnedd y Cribau (SH 676 536), Y Cribau (SH 673 533), Arenig Fawr (SH 827 369,
bwlch only), Pt. 574.9m (SH 663 500), Cerrig Cochion (SH 660 508),
Cerrig Cochion (SH 662 510) and Cerrig Cochion (SH 663 512)
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| Clogwyn Bwlch y Maen (SH 679 542) |
The central part of the
Moelwynion are reminiscent to parts of the Rhinogydd as they are rugged hills
with a feel of wilderness compared to their higher but easier underfoot
adjoining hills to the south.
Our aim was to visit and
survey all necessary hills between Clogwyn Bwlch y Maen in the north and a fine
slender ridge of a hill beside Llyn Edno in the south. We left one car in a lay-by for our descent
from Bwlch y Rhediad and continued north to leave the other car just beyond the
Pen-y-Gwryd Hotel.
As we walked back on the
road toward the footpath giving access to the western ridge of Moel Siabod a
blanket of light grey murk slowly pushed its pay up the valley from Capel
Curig, a foreteller of light rain that blew in for the first hour or so of the
walk.
It was good to be out with
Aled again, and today’s walk was a route he’d suggested which if successful
would fill in all surveying gaps on the way.
The first objective was the critical bwlch of Moel Siabod which Aled had
analysed via LIDAR data, and although I had come prepared with the ten figure
grid reference for its position it proved a decidedly boggy affair getting to
the point where the Trimble was set up.
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| Gathering data at the critical bwlch of Moel Siabod |
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| Looking down on the bwlch of Moel Siabod with the Pen-y-Gwryd Hotel on the right |
A path heads up from the
area of the bwlch toward our first hill of the day; Clogwyn Bwlch y Maen, which
is a fine hill dominated by its higher neighbours of Moel Siabod and Carnedd y
Cribau. The mist rolled in as we gained
height and light rain fell from a leaden sky, but with an improving forecast we
were optimistic for the remainder of the day.
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| A murky morning as the rain sweeps in |
Bi-passing the summit we
headed for its connecting bwlch to Moel Siabod and soon determined where its
critical point lay, and soon the Trimble was set up gathering its allotted five
minutes of data. Below the double lakes
of Llynnau Duweunydd glistened when flashes of sunlight pushed through the
easterly cloud bank, all round the higher hills were obscured under a murk, but
the morning’s rain had now ceased and slowly the cloud would rise and blue sky
appear as we continued heading southward.
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| Llynnau Duweunydd |
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| Gathering data at the critical bwlch of Clogwyn Bwlch y Maen |
The summit of Clogwyn
Bwlch y Maen consists of a small greened area a couple of metres from its ridge
fence, after the Trimble had gathered data we pressed on to the next connecting
bwlch which consisted of a large expanse of moor grass and bog.
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| Gathering data at the summit of Clogwyn Bwlch y Maen |
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| Gathering data at the critical bwlch of Carnedd y Cribau |
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| Clogwyn Bwlch y Maen with the cloud enshrouded Carneddau in the background |
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| Llynnau Duweunydd with Moel Siabod still in cloud |
I’d only visited Carnedd
y Cribau once before in August 2002 and remember it as a fine hill, substantial
and rocky at its top. It hasn’t
changed! Although the light grey murk
was disappearing the higher hills were still bathed in cloud and further east a
cloud blanket shielded all distant views inland, but thankfully even though
Carnedd y Cribau was our high point of the day it was free of cloud. Its summit consists of two large boulders a
few metres apart, both were Trimbled, and with the rock still slippy from the
recent rain the second one proved a little awkward to stand on top of, thankfully
both boulders proved relatively easy to set the Trimble up at their highest
point.
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| The first point surveyed for the summit of Carnedd y Cribau |
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| The view west from the summit of Carnedd y Cribau |
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| The second point surveyed for the summit of Carnedd y Cribau |
The southern ridge of
Carnedd y Cribau has a 557m map heighted bump on it and we wanted to survey it for
potential Uchaf status, although we both thought that the hill only had about
10m of drop. Once complete we headed down
steeply to the next bwlch which is the critical bwlch of Arenig Fawr and which
would later in the day also be our descent route, but that would have to wait a
few hours as ahead lay Cerrig Cochion.
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| Gathering data at the critical bwlch of Y Cribau with Aled waiting at its summit |
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| Gathering data at the summit of Y Cribau |
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| Aled heading toward the next bwlch which is that for Arenig Fawr |
Whilst at this bwlch
Aled set the Trimble up as he’d come prepared with a cunning plan of pressing
on to the hill beside Llyn Edno to survey its bwlch and summit, whilst I could
leisurely head toward Cerrig Cochion where he would join me doubling back
around the eastern part of Moel Meirch.
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| The upper slopes of Yr Wyddfa bathed in light as the mass of cloud begins to break |
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| Gathering data at the bwlch area of Arenig Fawr |
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| The shapely profile of Yr Aran |
He took all necessary
items, including the all-important Trimble, notebook, pen and steel tape, and
headed up beside the fence toward Cerrig Cochion, I followed with the intention
to meet him on a 540m ringed contour of a bump to the south of Cerrig Cochion
which map contours indicated was adjoined to Moel Meirch.
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| Aled heads off to fall in a bog, I follow and do likewise |
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| Gathering data at the critical bwlch of Pt. 574.9m (SH 663 500). Photo: Aled Williams |
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| Approaching the summit of Pt. 574.9m (SH 663 500). Photo: Aled Williams |
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| Gathering data at the summit of Pt. 574.9m (SH 663 500). Photo: Aled Williams |
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| Llyn Edno. Photo: Aled Williams |
I found the going tough
as the bog seemed unrelenting, however delicate my step and long my detour to
pass the worst of the bog I stepped on to what I thought to be semi-solid
ground and went almost knee deep in black slime. However, afterward when Aled re-joined me he
re-countered that he’d ended up almost waist deep in a bog and only got out as
he lunged toward the grass banks and grabbed a hold.
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| The hazards of trying to cross a bog |
If not for the fence
line and adjoined path this section of hill would be a wild affair as rock and
bog predominate. I made slow progress
and wondered if Aled would reach our rendezvous spot before me. By now Moel Siabod had cleared of cloud and
the warmth of the sun started to edge its way on to the land. I bi-passed the summit of Cerrig Cochion and
headed toward the 540m ringed contour lump to wait for Aled to appear on the
path to the east of Moel Meirch, which from this viewpoint looked an impressive
lump of rock jutting out of a desolate and beautiful moor.
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| Moel Siabod |
I waited for about 50
minutes, wrapped up in my Goretex shielding the slight breeze and the onset of
cold that would inevitably come due to inactivity. It was a marvellous place to sit and watch
the dappled shadow cast across the land.
Behind me to the north the rock strewn summit of Cerrig Cochion reared
up sun drenched and then shadowed as the play of light forever changed. To my south the rock bulk of Moel Meirch
reared against a foreground of quiet moor and bog.
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| Cerrig Cochion (SH 662 510) |
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| Cerrig Cochion flanked by Moel Siabod to its right |
Eventually Aled appeared
on the path heading back toward Cerrig Cochion having surveyed the hill beside
Llyn Edno, when he arrived he looked slightly dishevelled and recounted his
waist deep meeting with the bog. A
couple of minutes from where I had waited was the 540m ring contoured bump that
we now wanted to survey, the bwlch was soon complete and as the Trimble
gathered its customary five minutes of summit data I joined Aled close to a
cairn for a stunning view down and across Llyn Gwynant in the valley below.
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| Gathering data at the critical bwlch of Cerrig Cochion (SH 662 510) |
It was a slow plod to
the summit of Cerrig Cochion and the day’s exertions were beginning to tell. Once at the summit I positioned the Trimble
atop my rucksack aligned with the highest part of rock that I could find at the
base of the hill’s summit cairn, and wedged my rucksack in place with rocks as
it was delicately placed directly above a small drop.
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| Aled at the summit of Cerrig Cochion (SH 662 510) |
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| Just below the summit of Cerrig Cochion - a beautiful and delicate web |
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| The view west from the summit of Cerrig Cochion |
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| Gathering data at the summit of Cerrig Cochion (SH 662 510) |
All that remained from
our original surveying plan was a 530m ring contoured bump to the north of the
higher Cerrig Cochion summit, we had both visually dismissed this having passed
it earlier in the afternoon, and we both decided that it wasn’t worth surveying
as we re-joined the path beside the fence for our descent toward the horrendous
bog. However, as we passed its
connecting bwlch we stopped, checked the time, and as it was now beautifully
sunny with radiant blue sky and hardly a breath of breeze and as we now knew
that we had plenty of time for our descent we decided to survey it but only on
Aled’s insistence that the minimum two minutes of Data were gathered, I sneaked
three minutes at both its bwlch and summit!
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| The last bwlch survey of the day |
Whatever this last bumps
survey result it is a fine wee hill with an impressive and attractive summit
consisting on an elongated rock where the Trimble was delicately placed
collecting summit data. All that
remained was the descent back through the bog and down toward Aled’s car.
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| The last summit survey of the day |
Once past the bog it was
a magical descent with early evening low light casting beautiful colour as mist
caps descended on the higher mountains.
Away to the west a silver sheened land was now on view as the sun slowly
ebbed toward setting.
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| Late afternoon cloud on the high Glyderau |
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| Heading down to the valley below |
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| Moel Hebog with Llyn Gwynant in the forground |
The walk had taken almost
ten hours and we had surveyed 17 points in all.
Once back at the car I changed into dry clothes and Aled dropped me off
at mine, we waved our goodbyes and I headed down the A5 to treat myself to
chips and a number of accompaniments in Betws before heading toward Y Bala and
crossing the Y Berwyn. I stopped near
the high point of the road to look west toward coloured sky over the high peaks
of Eryri as reds merged with orange and mountain profiles merged with the land.
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| Sunset over Eryri |
Slowly the highlighted
reds with the darkened and delicately cloud capped profiles of the hills gave
way to subtle blues as the colour ebbed to darkened dusk, a lovely sight to end
a day.
Postscript:
Since surveying these hills full LIDAR coverage is now
available. The LIDAR (Light Detection & Ranging) technique
produced highly accurate height and positional data that is now freely
available for England and Wales. Consequently the numerical details
for these hills have been analysed using this technique, and where appropriate
LIDAR has been used in preference to that produced by the Trimble.
Survey Result:
Moel Siabod
Summit Height: 872.2m (from subsequent Trimble GeoXH 6000 survey)
Summit Grid Reference: SH 70524 54631 (from subsequent Trimble GeoXH 6000 survey)
Bwlch Height: 272.3m (converted to OSGM15)
Bwlch Grid Reference: SH 66044 55603
Dominance: 68.78%
Clogwyn Bwlch y Maen
Summit Height: 547.1m (converted to OSGM15)
Summit Grid Reference: SH 67908 54270
Bwlch Height: 525.2m (converted to OSGM15)
Bwlch Grid Reference: SH 68011 54318
Drop: 21.9m
Dominance: 4.00%
Carnedd y Cribau
Summit Height: 591.5m (converted to OSGM15)
Summit Grid Reference: SH 67617 53695
Bwlch Height: 507.0m (converted to OSGM15)
Bwlch Grid Reference: SH 67647 54133
Drop: 84.5m
Dominance: 14.29%
Y Cribau
Summit Height: 556.9m (converted to OSGM15)
Summit Grid Reference: SH 67383 53333
Bwlch Height: 546.4m (converted to OSGM15)
Bwlch Grid Reference: SH 67461 53359
Drop: 10.6m
Dominance: 1.90%
Arenig Fawr
Summit Height: 853.7m (LIDAR)
Summit Grid Reference: SH 82702 36943 (LIDAR)
Bwlch Height: 373.8m (LIDAR)
Bwlch Grid Reference: SH 66540 52253 (LIDAR)
Drop: 479.9m (LIDAR)
Dominance: 56.22% (LIDAR)
Pt. 574.9m
Summit Height: 574.9m (converted to OSGM15) (significant height revision)
Summit Grid Reference: SH 66301 50001
Bwlch Height: 552.9m (converted to OSGM15)
Bwlch Grid Reference: SH 66287 50113
Drop: 22.0m
Dominance: 3.83%
Cerrig Cochion
Summit Height: 543.5m (converted to OSGM15, Trimble GeoXH 6000)
Summit Grid Reference: SH 66011 50831 (Trimble GeoXH 6000)
Bwlch Height: 531.1m (converted to OSGM15, Trimble GeoXH 6000 adjusted height relative to LIDAR position)
Bwlch Grid Reference: SH 66041 50754 (LIDAR)
Drop: 12.4m (Trimble GeoXH 6000 summit and Trimble GeoXH 6000 adjusted bwlch height relative to LIDAR position)
Dominance: 2.28% (Trimble GeoXH 6000 summit and Trimble GeoXH 6000 adjusted bwlch height relative to LIDAR position)
Cerrig Cochion
Summit Height: 548.9m (converted to OSGM15)
Summit Grid Reference: SH 66250 51062
Bwlch Height: 524.6m (converted to OSGM15)
Bwlch Grid Reference: SH 66174 51012
Drop: 24.3m
Dominance: 4.42%
Cerrig Cochion
Summit Height: 533.0m (converted to OSGM15)
Summit Grid Reference: SH 66395 51267
Bwlch Height: 519.8m (converted to OSGM15)
Bwlch Grid Reference: SH 66361 51202
Drop: 13.1m
Dominance: 2.47%
