25.08.18 Mynydd Ton (SS 949 940)
Mynydd Ton has a
convoluted history for summit placement as it was originally given to where its
535m map heighted trig pillar is situated; its summit position was then moved
to an ancient cairn where a 1,769.3ft (539m) surface height is given on the
series of Ordnance Survey Six-Inch maps, this latter position was surveyed
using the Trimble GeoXH 6000 in July 2016 as being 534.2m in height, therefore dependent
upon the flush bracket accuracy the ground at the base of the trig pillar will be
higher, therefore the summit was relocated back to that of the triangulation
pillar. Today we hoped to gather data
from ground beside the trig pillar and compare this against the data previously
taken from beside the ancient cairn.
As Mark, Aled and I set
off up the gravelled track that leaves the road junction between the A4061 and
the A4107, the distinctive profile of Corn Du and Pen y Fan were silhouetted
against a foreground of sparkling white wind turbines as the terraced rows of
houses in Cwmparc stood bolt upright in the valley below.
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| The distinctive profile of Corn Du and Pen y Fan in the background with the regimented houses of Cwmparc in the valley below |
Gaining height on the
wide track the roads below meandered around adjacent hillsides, with the mast
and wind turbines on Werfa to our west being a distinctive landmark, by now the
sun was relatively low in the sky casting delicate and appealing colour on the
land.
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| Meandering roads and wind turbines atop Werfa |
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| Looking out toward Werfa |
Leaving the track we
followed a path toward the conifer plantation that swamps the eastern part of
this hill, adjacent to this the path followed the forest’s perimeter fence
toward a wide forest break that heads east toward the summit of the hill. The last time I was here an abandoned 4x4
vehicle added unfortunate novelty to the scene, thankfully this has now gone
but some of its remains are still scattered across the grassland of the wide
forest break.
Our first port of call
was the trig pillar which is relatively easy to find amongst the trees as an
avenue has been cut leading to its secluded grove, and almost Narnia like it
nestles in its small clearing where once open hillside would have given
extensive views.
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| Entering the avenue of conifers leading to the secluded grove where the trig pillar is situated |
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| The trig pillar in its secluded grove |
We assessed the land at
the base of the trig pillar and once the position of the high point was determined
I placed the Trimble on top of the trig and took a measurement offset to the
summit, we now waited for it to slowly ebb
down toward its 0.1m accuracy level.
A five minute data set was gathered from the summit and we then left
through the enclosed avenue of cultivated conifers to the open forest break.
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| Gathering data at the summit of Mynydd Ton |
As data had previously been
gathered from beside the ancient cairn we opted for a second data set in the
wide forest break close to the perimeter fence, we had assessed this land when heading
toward the trig pillar and judged it to be slightly higher than that beside the
ancient cairn. Having walked back on the
forest break from close to the trig pillar we also thought this to be close in
height to that beside the trig.
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| Beside the ancient cairn |
Therefore as Mark and
Aled stood beside the perimeter fence watching the sun slowly sink in the
western sky I positioned the Trimble atop its improvised tripod of my rucksack
and gathered the last data set of the day.
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| The Trimble set-up position and the last data set of the day |
Once the Trimble was
packed away I joined Mark and Aled and stood and admired the scene of setting
sun with the view as far as the hills of south-west England rising above the
Bristol Channel.
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| Looking out toward the hill's of south-west England |
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| Watching the sun set behind Werfa |
To our west the mast and
wind turbines on Werfa gave dimension to the hill and added detail to a scene
of delicate colour that slowly unfolded from the oranged hues of a sinking sun
to the pinks and mauves when light tranquilly disappears.
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| A myriad of colour as the sun slowly disappeared behind Werfa |
It had been another enjoyable
day on the hill in good company with all our bagging needs met, but it had also
been a long day as after a quick stop in Brecon for chips it meant a late night
for all of us, with Aled heading back to Porthmadog from Caersws where his car
was parked, and Mark heading home to Mold after having a quick cup of coffee
when we arrived back at my home in Welshpool.
Survey Result:
Mynydd Ton
Summit Height: 534.4m (converted to OSGM15) (significant height revision)
Summit Grid Reference: SS 94931 94059 (summit relocation confirmed)
Bwlch Height: 443.1m (converted to OSGM15, previously
Trimbled)
Bwlch Grid Reference: SS 93953 94456
Drop: 91.3m
Dominance: 17.08%
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