26.11.20 Moel yr Henfaes (SJ 077 385), Y Drum (SJ 082
378), Pt. 581.7m (SJ 086 373) and Cefn Dylif (SJ 089 369)
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Y Drum (SJ 082 378)
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For many years it was as
if I was walking with blinkers on, as I concentrated on the higher 2,000ft
mountains and rarely ventured to any hill that was lower. It was the listing of the Deweys that opened my
eyes to the lower hills, closely followed by the remaining Twmpau. And two hills on today’s walk show how
blinkered my vision was, as the first hill; Moel yr Henfaes I had only visited
once before in August 2000, whilst the last hill; Cefn Dylif I had visited on
21 occasions. Both hills are on the same
ridge, with the former at its north-westerly end and the latter joining the
main Berwyn ridge. But the difference in
totals is purely down to height.
I was joining Mark and
Aled for this walk and the arrangements to meet and route and hills to visit
were quickly organised the preceding evening.
We met in Cynwyd and took two cars to the end of a steep minor road and
parked beside the farm buildings at Rhos-y-maerdy. This was at 350m, which helped somewhat.
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The way to the hill
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I set off a few minutes
before the others and made my way up the track that continues from the end of
the paved road. Conditions were beautiful
with the remnants of mist still in the valley below and the higher Berwyn tops clear
with autumnal blue sky above, whilst further to the north and west many of the
higher tops were cloaked in a blanket of grey.
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The view west with mist in the valley and a grey murk over the higher tops
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Breaking away from the
track a field led up beside the Nant y Cwm toward the bwlch between Moel yr
Henfaes and Y Drum, in time this would be surveyed, but our first objective was
the summit of Moel yr Henfaes. I heard Mark
and Aled before I could see them, with their voices echoing against the
stillness of the morning. By the time
they emerged on to the field below I was now immersed in heather, making slow,
rough progress ever upward.
An occasional sheep path
amongst the heather helped, but in the main it was rough and pathless. Bit by bit height was gained and I eventually
reached the ridge and swung left up toward the summit. Within a minute or so of arriving on top I
was joined by Mark and Aled.
As the Trimble gathered
summit data we sat and stood close to the cairn in the morning sunshine looking
out across a myriad of hills, some clear, others still cloaked in grey, but all
inviting.
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Gathering data at the summit of Moel yr Henfaes
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It was only a short
distance back toward the connecting bwlch which is the critical one for the
next hill on the ridge; Y Drum. This was
in a sea of tussock grass and heather and as I stood knee deep in the stuff Mark
used his hand-held GPS to zero in to where the 551m spot height appears on the
ground. The whole area was awash with
large tussocks and this was our best way to approximate where the bwlch
lay. Before setting the Trimble up, I
assessed the lay of land and as I positioned the equipment on top of my
rucksack, Mark and Aled headed toward the summit of Y Drum.
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Gathering data at the bwlch of Y Drum
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Once data were gathered
and stored I closed the equipment down, packed it away and stumbled my way to a
part of the hill where the heather had been cut, this at least enabled easier
underfoot conditions, and the temptation of a grazed and closely cropped grassy
field was not too far away. This I
reached and within a couple of minutes I joined the others at the summit.
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Moel yr Henfaes (SJ 077 385)
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The summit of Y Drum is
attractive and consists of a small rocky knoll.
After setting the Trimble up to gather data we each sat, socially
distanced on a rocky rib that extended out from the summit area. A few minutes later it was time to head off
again, this time down to the bwlch that is the critical one for Moel yr Henfaes.
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Gathering data at the summit of Y Drum
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I headed off before the
others and had the Trimble set up gathering data as they waved and headed past
me up toward the summit of a 582m map heighted hill that had recently been promoted
to Sub-Uchaf status. The proceeding
summit and bwlch survey will confirm its status one way or the other.
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Gathering data at the bwlch of Moel yr Henfaes
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Its summit was beside
the ridge fence overlooking a steep drop down to its bwlch. By the time I arrived at its high point, Mark
and Aled had assessed the lay of the land and chosen the place for Trimble
placement. As the equipment gathered
summit data, Aled headed down to assess the bwlch. Once data were gathered and stored I joined
him, whilst Mark headed off and waited for us just beyond the bwlch.
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Mark and Aled heading to the summit of what used to be a 500m Sub-Uchaf
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We took two data sets
from the area of the bwlch, each on the hill to hill traverse. The ground above and to our north was steep, and
whilst the Trimble gathered its sixth and seventh data set of the day we
debated whether this hill would retain its sub status.
Only one hill remained
to survey and after closing the equipment down I followed Mark and Aled up a
vehicle track on the moor toward a fence and then across it to the rocky rib
and cairn that make up the summit of Cefn Dylif. The last time I had visited this summit was
in August 2007, a lot has changed in my life since then, some good, some not so
good, and although it is clichéd to say; the allure of the hills remain as a
constant.
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Gathering data at the summit of Cefn Dylif
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After the summit was
surveyed we headed down to the bwlch which has the continuation of our inward
track crossing it, before it continues down following the course of the Nant
Rhydwilym to the Afon Ceiriog. It was
easy to pinpoint the critical point and as the Trimble was set up Mark and Aled
went to find the book beside the memorial to the Wayfarer.
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Gathering data at the bwlch of Cefn Dylif
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Many years ago a form of
garage stood at this bwlch, its roof finally gave up and collapsed and now any
lingering remnants have been removed. It
leaves this part of the Berwyn garage free, and all the better for it.
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The Wayfarers Memorial
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The bwlch survey was the
ninth data set of the day and once safely stored I closed the Trimble down,
took a few photos and packed it away and we headed down the track back to the
awaiting cars. It had been another good
day on the hill.
Postscript: Since the survey of these hills with the Trimble GeoXH 6000 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. Y Drum and Cefn Dylif have also been surveyed by Alan Dawson using a Leica RX1250. Therefore, it is a combination of these surveying methods that form the listed data.
Survey Result:
Moel yr Henfaes
Summit Height: 584.5m (converted to OSGM15)
Summit Grid Reference: SJ 07755 38589
Bwlch Height: 547.4m (converted to OSGM15)
Bwlch Grid Reference: SJ 08418 37600
Drop: 37.1m
Dominance: 6.34%
Y Drum
Summit Height: 579.1m (converted to OSGM15, Trimble GeoXH 6000 and Leica RX1250)
Summit Grid Reference: SJ 08247 37893 (Trimble GeoXH 6000 and Leica RX1250)
Bwlch Height: 549.1m (converted to OSGM15, Leica RX1250)
Bwlch Grid Reference: SJ 07986 38259 (Leica RX1250)
Drop: 30.0m (Trimble GeoXH 6000 and Leica RX1250 summit and Leica RX1250 bwlch) (500m Sub-Twmpau reclassified to 500m Twmpau) (Dewey addition)
Dominance: 5.18% (Trimble GeoXH 6000 and Leica RX1250 summit and Leica RX1250 bwlch)
Pt. 581.7m
Summit Height: 581.7m (converted to OSGM15)
Summit Grid Reference: SJ 08664 37360
Bwlch Height: 568.7m (converted to OSGM15)
Bwlch Grid Reference: SJ 08659 37320
Drop: 13.0m (500m Sub-Uchaf deletion)
Dominance: 2.23%
Cefn Dylif
Summit Height: 618.5m (converted to OSGM15, Leica RX1250) (significant height revision)
Summit Grid Reference: SJ 08943 36943 (Leica RX1250)
Bwlch Height: 581.3m (converted to OSGM15, Trimble GeoXH 6000)
Bwlch Grid Reference: SJ 09068 36590 (Trimble GeoXH 6000)
Drop: 37.3m (Leica RX1250 summit and Trimble GeoXH 6000 bwlch)
Dominance: 6.03% (Leica RX1250 summit and Trimble GeoXH 6000 bwlch)
For further details please consult the Trimble Survey Spreadsheet
