11.03.18 Garreg Amlwg (SH 717 549), Moel Siabod (SH 705
546), Pt. 815.9m (SH 708 550), Pt. 811.2m (SH 709 551) and Pt. 800.8m (SH 711
552)
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| Garreg Amlwg (SH 717 549) |
For many years it seemed
as if I was walking with blinkers on, being preoccupied with the 2,000ft
mountains of Wales with little regard for visiting lower heighted hills. Nowadays I get pleasure enough on the lower
P30s, but when opportunity arises to visit the higher hills their dramatic
architecture is savoured, and today was such an occasion as along with Mark and
Aled we planned on visiting Moel Siabod and a number of lower satellite peaks
whose existing and potential P15 status needed clarifying.
Moel Siabod is a
wonderful hill set apart from its higher neighbours, its 872m map heighted
summit commands extensive views and is a relative recent addition to Mark’s
P600 Majors list, only entering this list as the 272m bwlch spot height that
appears on the Ordnance Survey Interactive Coverage Map hosted on the Geograph
website gives the hill 600m of map spot heighted drop.
Having left three cars
at different points for optional descent routes we ascended via Pont Cyfyng,
walking up the narrow lane to the footpath gaining the track leading to the
north-eastern ridge of Moel Siabod, across the valley spring sunshine picked
out the rugged profile of Creigiau Gleision and the pyramidal shape of Pen
Llithrig y Wrach. However, the sunshine
was not to last as high greying cloud would slowly ebb in from the south adding
wisps to the higher tops with the prospect of incoming rain.
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| Creigiau Gleision |
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| Pen Llithrig y Wrach |
The first hill we wanted
to investigate is listed as an Uchaf, these are the Welsh P15 hills at and over
500m in height, and the hill only entered this list through a basic levelling
survey conducted in July 2004. Following
a path toward a quarry lake the hill rose above slightly rounded and elongated
in profile it sits away from its much higher neighbour and is probably seldom
visited and yet it is situated in a marvellously wild landscape of heather
moor, bog and rock.
Moel Siabod looked
dramatically appetising as we descended to the hill’s connecting bwlch which
has a number of small attractive pools situated on it, we judged where the
critical bwlch lay and as I set the Trimble up and floundered in the overly wet
bog adjacent to the larger of these pools, Mark and Aled headed off to
investigate if there was an outflow from the opposing side of the pool.
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| Descending to the connecting bwlch of Garreg Amlwg |
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| Mark with Moel Siabod as backdrop |
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| Gathering data at the area of the bwlch of Garreg Amlwg |
This hill has two tops
and both were Trimbled, with each summit consisting of a large rock. As the more north-westerly top was Trimbled
Mark and Aled visited the south-easterly one, I looked out as they waited on
this summit with the cliff face of Moel Siabod as backdrop rising skyward
dwarfing our position.
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| Gathering data from what proved to be the lower of the two tops |
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| Aled and Mark on the south-westerly top of Garreg Amlwg |
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| Gathering data from the summit of Garreg Amlwg |
Leaving the hill we
followed a narrow path across the outflow from Llyn y Foel and joined the lower
part of Daear Ddu, which if wanting a scramble is the way to approach Moel
Siabod. Daear Ddu is the eastern ridge
of Moel Siabod and I’ve enjoyed its rock on many occasions, the first being
with a horrendous hangover when I was sick on the hill, not a pretty sight!
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| Beside Llyn y Foel |
As height was gained the
view opened, down upon Llyn y Foel and across the Eryri peaks to the far off
Berwyn and Bryniau Clwyd. The ridge was
fun, as it ever is, with just enough hand on rock to bring a sustainable amount
of enjoyment.
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| Llyn y Foel |
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| The north-eastern ridge of Moel Siabod with the three tops which were later surveyed |
By the time we crested
the summit ridge cloud had built and as the Trimble clung aligned to the
highest rock gathering its all-important data, mist quickly rolled in and would
remain with us until we descended.
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| The north-eastern ridge from close to the summit of Moel Siabod |
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| The view south-west just before the mist rolled in |
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| Gathering data at the summit of Moel Siabod |
If time permitted we
hoped to survey at least two of the three tops on the upper part of the
north-easterly ridge of Moel Siabod, each is a jumble of rock with two of the
three bylchau being tight with plunging drops nearby down horrendously steep gulleys.
After the Trimble had
gathered its allotted data from the summit of Moel Siabod I joined Mark and
Aled in the large wind shelter just below the high point for a bite to eat
before continuing to the three rocky tops.
As we walked through the
mist toward the first connecting bwlch we discussed the merits of what ones to
survey as dusk would be approaching on our descent and as the weather had
closed in it looked as if the forecast rain would overtake us, these weren’t
ideal conditions to survey castellated summits above mighty drops. The impending problem was solved when Aled
suggested a two minute data set at each bwlch and summit, this is the minimum
suggested for data collection by Trimble.
This would enable the three tops to be surveyed in turn and would
complete all tops adjoined to Moel Siabod then having been Trimbled.
The ridge proved fun as
the rock was damp with rock step after rock step negotiated from one summit to
bwlch and onward to the next summit.
These surveys came thick and fast with barely a moment to contemplate
some of the Trimble bwlch positions with two being on the edge of mountainous
drops down steep gulleys.
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| A precarious position for a Trimble |
As the last summit was
Trimbled Mark headed down to a fence which gave access to the path leading to
where one of our cars was parked beside Plas y Brenin and Llynnau Mymbyr, Aled
and I soon followed.
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| Gathering data from the summit of Pt. 800.8m |
It had been a good day
on the hill with ten surveys completed, with an enjoyable time picking out an
occasional scramble whilst visiting the summit of one of Eryri’s special
mountains. We ended the day in the Bryn
Tyrch at Capel Curig with good conversation and a welcome meal.
Postscript: Since the
survey of these hills, the LIDAR (Light Detection & Ranging) technique is
now being used to produce accurate height and position for hills.
Therefore, numerical data produced by surveying with the Trimble GeoXH 6000 is
being updated. However, each individual data set is analysed and as data
produced by the Trimble GeoXH 6000 is considered more accurate it is this
relative to the position produced by LIDAR that is prioritised.
Survey Result:
Garreg Amlwg
Summit Height: 561.6m (converted to OSGM15, Trimble GeoXH 6000)
Summit Grid Reference: SH 71781 54962 (Trimble GeoXH 6000)
Bwlch Height: 546.5m (converted to OSGM15, height relative to Trimble GeoXH 6000)
Bwlch Grid Reference: SH 71748 55025 (LIDAR)
Drop: 15.1m (Trimble GeoXH 6000 summit and LIDAR with height relative to Trimble GeoXH 6000 bwlch)
Dominance: 2.76%
Moel Siabod
Summit Height: 872.2m (converted to OSGM15)
Summit Grid Reference: SH 70524 54631
Bwlch Height: 272.3m (converted to OSGM15) (from previous Trimble GeoXH 6000 survey)
Bwlch Grid Reference: SH 66044 55603 (from previous Trimble GeoXH 6000 survey)
Drop: 599.9m (P600 Major deletion)
Dominance: 68.78%
Pt. 815.9m
Summit Height: 815.9m (converted to OSGM15)
Summit Grid Reference: SH 70859 55036
Bwlch Height: 808.9m (converted to OSGM15)
Bwlch Grid Reference: SH 70797 54991
Drop: 7.0m
Dominance: 0.86%
Pt. 811.2m
Summit Height: 811.2m (converted to OSGM15)
Summit Grid Reference: SH 70955 55120
Bwlch Height: 803.9m (converted to OSGM15)
Bwlch Grid Reference: SH 70898 55084
Drop: 7.3m
Dominance: 0.90%
Pt. 800.8m
Summit Height: 800.8m (converted to OSGM15)
Summit Grid Reference: SH 71115 55231
Bwlch Height: 787.5m (converted to OSGM15)
Bwlch Grid Reference: SH 71076 55224
Drop: 13.3m
Dominance: 1.66%
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