13.09.19
Aran Fawddwy (SH 862 223), only bwlch surveyed
Aran Fawddwy is the
highest hill in Britain south of Yr Wyddfa and as such it dominates the land
around it. The view from its summit is
extensive with ridge upon ridge of diminishing hills to its east and the higher
Eryri hills far off to its north. I’d
visited its summit 19 times but had never visited its bwlch, although I had
driven over it on many occasions. This
bwlch is positioned beside the A494 road as it makes its way from Dolgellau in
the south-west to Y Bala in the north-east.
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| Aran Fawddwy (SH 862 223) |
The bwlch is unassuming,
as many bylchau are. Outside of the many
vehicles that pass over it on a daily basis I wonder if anyone has ever visited
it because of what it is. I suspect not.
Prior to my visit Aled
Williams had LIDARed the bwlch and afterward I did likewise. I also drove a Google car in the vicinity of
the bwlch to compare the placement of the bwlch via LIDAR to the lay of land
via a digitised image, and found by parking at the entrance to Pant Gwyn on the
western side of the road it would enable me to position the car directly over
the position of the bwlch according to LIDAR.
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| LIDAR bwlch image for Aran Fawddwy |
I arrived mid-afternoon
and manoeuvred my car in to position leaving sufficient space for any vehicle
driving in or out of Pant Gwyn, and importantly with the front of the car
safely positioned off of the main road.
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| The car in place with the Trimble on its roof |
Also crossing this point
is the disused railway line that connected Dolgellau to Y Bala, its course can
easily be seen either side of the road and before setting the Trimble up to
gather data I wanted to investigate the land beside the road. My conclusion is that the building of the rail
line and road has increased the height of this bwlch from its natural point,
but determining the natural height and its position is now probably impossible,
therefore I concentrated on the LIDAR position and aligning the Trimble with it
as it was placed on top of my car’s roof.
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| The set-up position beside the grass verge next to the drive leading to Pant Gwyn |
Once the offset between
the Trimble’s internal antenna and the ground below was measured and noted, I
created the file and waited for the 0.1m accuracy level to be attained and then
pressed ‘Log’ and waited for the allotted data to be gathered and stored.
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| Gathering data at the bwlch of Aran Fawddwy |
During this I stood back
and watched the steady hum of cars hurtle past whilst enjoying the afternoon
sunshine. After the Trimble was closed
down a vehicle appeared from Pant Gwyn, I went over to say hello and explain
what I was doing, and the occupant said she did wonder. We chatted for a number of minutes and she
explained that her family farm from Rhyd-y-main and I wondered if I had made
place-name enquires with her husband during the extensive enquiries with local
famers when I covered the Aran range.
After I packed the
Trimble and the surveying steps away I waved my goodbye’s and headed toward Y
Bala and the B4391 road crossing the Y Berwyn for the last survey of the day.
Survey Result:
Aran Fawddwy
Summit Height: 905.6m (Leica RX1250)
Summit Grid Reference: SH 86270 22386 (Leica RX1250)
Bwlch Height: 232.7m (converted to OSGM15)
Bwlch Grid Reference: SH 85050 26799
Drop: 672.9m
Dominance: 74.30%
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