06.07.19 Elidir Fawr (SH 611 612), Foel Goch (SH 628
612), Mynydd Perfedd (SH 623 618), Carnedd y
Filiast (SH 620 627) and Fronllwyd (SH 617 631)
Elidir Fawr (SH 611 612) |
Having arrived at the end of the paved public road that makes its way toward the Marchlyn Mawr Reservoir, Aled and I sat in the car for almost two hours watching the constant drizzle and low cloud envelop the land. The drizzle soon developed in to rain and the thought of heading out in these conditions did not enthuse me. However, as the forecast predicted better conditions late morning and clearing for the afternoon we eventually donned our waterproofs and headed over the locked gate to the continuation of tarmac that led forever upward toward the reservoir and low cloud.
We had prepared for
another survey, but with the ground so wet and the cloud base low, we decided
that conditions were not favourable and this particular hill could wait for
another day and a round taking in Elidir Fawr and ending on Fronllwyd was
feasible.
The paved road ends at
the Marchlyn Mawr Reservoir and from here we joined the narrow path that
ascends the northern ridge of Elidir Fawr.
The circuit ahead of us used to be one that I did frequently and always
enjoyed, as it includes five hills and gives variety and good views, today with
clag on the hill we were in no rush and slowly plodded our way up in to the
mist, eventually cresting the hill’s eastern ridge close to the summit. Here we came upon two marshals who were a
part of the Snowdonia Seven which is the most challenging sporting event in the
Police’s calendar. We stood and chatted
with them; a father and daughter, for a number of minutes, they explained that
the leaders had just passed by, soon the next group of four competitors
appeared and headed further in to the mist toward the top of Elidir Fawr. We also soon followed.
The summit of Elidir
Fawr has a large wind shelter on its ridge with the high point further south-west
and crowned by an untidy cairn. Positioned
in the wind shelter Aled used an Abney level to confirm the highest rock and
within a couple of minutes the Trimble’s internal antenna was aligned with it and
gathering its customary five minutes of data.
Gathering data at the summit of Elidir Fawr |
I’d come prepared with a series of ten figure grid references for each summit and bwlch that we may visit, and having packed the Trimble away we headed back toward the two marshals as more teams of four kept appearing through the mist on their way toward the summit of Elidir Fawr. Our next point to survey was the connecting bwlch ahead of us; this is named Bwlch y Marchlyn on Ordnance Survey maps and is adjoined to Carnedd y Filiast. The main path heading toward it contoured around the upper part of Cwm Dudodyn missing the castellated crest of the ridge and the actual bwlch, and initially so did we in the mist, when close to it we scrambled up a steep mudded gully and checked the grid reference in the Trimble, the critical point of the bwlch was a few metres behind us and thankfully relatively open for satellite reception and easy to position the Trimble on. As it gathered data I stood on the northern part of the narrow ridge overlooking steep ground plunging down toward the reservoir, happy in the knowledge that progress was being made even though the weather conditions were not ideal.
Gathering data at the bwlch of Carnedd y Filiast |
Once I re-joined Aled we continued on the main path around the upper cwm toward our next hill; Foel Goch, which rears up steeply from this vantage point, however all we could see were dark misted shapes with outlines of hills and crests of near ridges.
On our way toward Foel
Goch the first signs of rising mist started to develop as land appeared, this
gave us a chance to assess where the critical bwlch for Elidir Fawr was placed;
this is positioned at the north-western base of Foel Goch and beside the ridge
fence as the drop plunges down to Nant Ffrancon. Leaving the bwlch survey for afterward we
continued toward our next hill.
A very grey looking Bwlch y Marchlyn |
Just as we started the ascent of Foel Goch, Aled helpfully informed me that we had almost 400ft of uphill immediately above us. I put my head down, reached a trance like state and very slowly plodded up. My pace was extremely slow but I managed the whole uphill without stopping, which pleased me. At the top we came upon two other marshals and very soon a number of other participants in the Snowdonia Seven, unfortunately the marshals were now sweeping up the stragglers with many who appeared on the top of Foel Goch having been timed-out from the challenge.
I’d always accepted the
small cairn close to the shear drop on the northern end of the summit ridge of
Foel Goch to be at its high point, it isn’t, although it was Trimbled. The summit is a few metres away to the south,
and this was also Trimbled. During this
Aled went hunting for alpine plants and showed me a dwarf tree, related to the
willow and no more than delicate green leaves dewed by drizzle and nestled
against the ground.
The first data set beside the small cairn atop the summit of Foel Goch |
Gathering data at the summit of Foel Goch |
As we left Foel Goch the mist started to rise again, giving views toward Elidir Fawr and the bwlch below and the land beyond comprising the summit of Mynydd Perfedd. It looked as if the conditions were now improving and the rest of the walk would be free of cloud. Unfortunately the mist soon descended again and kept us in its grip for a while longer. However, we did have chance to assess the lay of land for the bwlch at the north-western base of Foel Goch which is the one adjoined to Elidir Fawr, and a further Trimble data set was gathered from it.
At Bwlch y Brecan with Mynydd Perfedd in the background |
Gathering data at the bwlch area of Elidir Fawr |
Foel Goch from Bwlch y Brecan |
A path heads from this bwlch steeply up to the summit of Mynydd Perfedd and I slowly followed Aled and joined him beside the spike of rock a few metres from a large wind shelter which constitutes the high point of this hill. We soon devised an ingenious way to position the Trimble so it was secure and aligned with the highest part of the spike of rock and stood beside the wind shelter as it gathered its all-important data.
An ingenious way to gather data at the spike of rock signifying the high point of Mynydd Perfedd |
Beyond Mynydd Perfedd are the higher Carnedd y Filiast and the lower Fronllwyd, I’d wanted to survey these hills and also the ones we had already visited ever since getting the Trimble, but especially Mynydd Perfedd to establish an accurate drop value for the hill and to establish an accurate height for Fronllwyd; a hill that I had previously surveyed many times but always for its drop value and up until today never for its height.
We surveyed two points
for the bwlch position of Mynydd Perfedd with the second obviously lower than
the first, but as it was still misty when we arrived at the first point we did
not realise this until collecting data and packing the Trimble away, as we
headed on the continuation of the path toward Carnedd y Filiast the mists
started to rip apart and ahead of us was obvious lower ground.
Gathering data at the bwlch of Mynydd Perfedd |
The mists start to clear on Mynydd Perfedd |
Only two summit surveys remained and the first consisted of a large rock amongst the untidy cairn atop Carnedd y Filiast. After Aled had used the Abney level to pinpoint the highest rock I set the Trimble up and looked beyond the wind shelter where Aled was now sitting as the distant view further west opened up, and after being in mist for most of our walk the view was to be savoured.
Gathering data at the summit of Carnedd y Filiast |
Leaving the summit of Carnedd y Filiast we followed the path down to the connecting bwlch with Fronllwyd, this hill was the first that John, Graham and I surveyed as a threesome using John’s level and staff to do so, and it was one of two hills that I lobbied John and Anne Nuttall to survey as the measurements I had ascertained gave the hill over 15m of drop. They only accepted its inclusion in their list after the line survey, although it had already entered the list of Welsh hills at and above 500m in height that have 15m minimum drop which is now co-authored with Aled.
As Fronllwyd had been
line surveyed for drop its summit only required an accurate height and
therefore the bwlch was not Trimbled.
The summit comprises a pointed large rock that can easily be stood on
top of, but proves a little awkward to backtrack down from. I balanced a rock on the upper part of the
summit rock, made sure it remained in place and proceeded to balance the
Trimble on it with its internal antenna fixed to the very highest part of
pointed rock. It proved a delicate
balancing act and one that would not have been attempted if there was any
breath of breeze, thankfully there was none and the Trimble remained in place
beeping away seemingly floating and aligned all at once. Needless to say I took many photos!
Gathering data at the summit of Fronllwyd |
The Trimble delicately balanced on the high point of Fronllwyd with Elidir Fawr in the background |
As we waited for the Trimble to gather its allotted data blue skies appeared with high wisps of cloud and a vivid hue to the emerging colour. Carnedd y Filiast now shone back radiant in the early evening light, as did Elidir Fawr as the last vestiges of cloud were ripped from its summit.
Carnedd y Filiast |
It is always wonderful to be on a summit after hours spent in mist when it clears and views open, but today with the vividness of colour and evening warmth it proved magical.
After packing the
Trimble away we joined the narrow path leading down the southern slopes of
Fronllwyd to the paved road close to Marchlyn Mawr Reservoir for our easy walk
back to Aled’s awaiting car.
Postscript
Since visiting 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, resulting in the LIDAR height
and position being prioritised for some of these hills.
Survey Result:
Elidir Fawr
Summit Height: 922.3m (converted to OSGM15, Trimble GeoXH 6000)
Summit Grid Reference: SH 61172 61288 ( Trimble GeoXH 6000)
Bwlch Height: 711.1m (LIDAR)
Bwlch Grid Reference: SH 62566 61555 (LIDAR)
Drop: 211.2m ( Trimble GeoXH 6000 summit and LIDAR bwlch)
Dominance: 22.90% ( Trimble GeoXH 6000 summit and LIDAR bwlch)
Foel Goch
Summit Height: 831.0m (converted to OSGM15, Trimble GeoXH 6000)
Summit Grid Reference: SH 62861 61200 ( Trimble GeoXH 6000)
Bwlch Height: 754.0m (LIDAR)
Bwlch Grid Reference: SH 62711 60231 (LIDAR)
Drop: 77.0m ( Trimble GeoXH 6000 summit and LIDAR bwlch)
Dominance: 9.27% ( Trimble GeoXH 6000 summit and LIDAR bwlch)
Mynydd Perfedd
Summit Height: 812.8m (converted to OSGM15)
Summit Grid Reference: SH 62319 61877
Bwlch Height: 792.4m (converted to OSGM15)
Bwlch Grid Reference: SH 62267 62382
Drop: 20.4m (800m Sub-Tumpau addition)
Dominance: 2.51%
Carnedd y Filiast
Summit Height: 823.6m (converted to OSGM15) (significant height revision)
Summit Grid Reference: SH 62040 62733
Bwlch Height: 744.4m (converted to OSGM15)
Bwlch Grid Reference: SH 61995 61535
Drop: 79.1m
Dominance: 9.61%
Fronllwyd (significant name change)
Summit Height: 720.8m (converted to OSGM15)
Summit Grid Reference: SH 61747 63161
Bwlch Height: 704.6m (relative to Trimble summit and line
survey for drop)
Bwlch Grid Reference: SH 61858 63028 (LIDAR)
Drop: 16.1m (line survey)
Dominance: 2.24%
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