07.09.15
Bryn y Fedwen (SN 840 953 – previously Trimbled), Mynydd Cil Cwm (SN 859
964), Bryn y Fedwen (SN 851 972), Moelfre (SN 848 983), Llannerch yr Aur (SN
863 978) and Banc Bron Derwgoed (SN 871 987)
Moelfre (SN 848 983) |
The architectural form
carved out when the glaciers receded in the last ice age left the northern
lands of the Pumlumon range of hills with a beauty all to themselves. These northern lands extend from their higher
and better known hills to a cascade of plunging drops and infrequent trodden
summits. It was a part of this northern
land that Aled and I wanted to investigate today.
We met in Llanbrynmair
in the early afternoon and left one car at the top of a minor road above Cwm
Nant Heli at Bwlch Glynmynydd (SN 866 992) and proceeded to drive toward
Dylife, only stopping to admire the view down into the bowl of land where the
Afon Twymyn flows from the hidden Ffrwd Fawr waterfall.
The Pennant Gorge - sublime as ever |
The forecast for the day
was excellent with sunshine and a hint of light breeze and as we parked beside
the entrance track to the Glaslyn Nature Reserve the colours shone from the
surrounding hills.
Our planned walk was
over two Uchafion, with one being a marginal, and three Pedwarau, with two
being marginal and the third classified as a Hump with 106m of drop, so there
would be lots of scope for status change with all except for our first hill
planned to be Trimbled. This first hill
is named Bryn y Fedwen on current Ordnance Survey maps and as I had previously
Trimbled it when on a walk with Eryl on 09.01.14 I did not plan to do so again
on today’s walk.
Once Aled’s van was
parked we were soon on the summit of our first hill which although the highest
of the day was certainly not the best.
The continuation of the route headed north-east following the line of a
fence, off in the distance a tractor chugged its way up and then down a field
where our route was taking us, as we approached, it was on a downward cycle and
we didn’t have the pleasure of a chat with a local farmer and just heard the chug,
chug as it went about its business.
Aled approaching the summit of the highest hill of the day, named as Bryn y Fedwen on the map |
We had a fleeting
inspection of the connecting land at the bwlch as we walked toward the summit
of our second hill; Mynydd Cil Cwm. I’d
visited this hill once before as a quick there and back from the convenience of
a track from the high road where we had parked and remembered its summit to be
heather bound, this is a confliction as it was set against reclaimed grazing
land with its greenness butting up against the purples and soft feel of hill
heather.
Two aspects of Mynydd Cil Cwm - the first from our approach to the summit..... |
......and the second shows the western side of Mynydd Cil Cwm above the Pennant Gorge |
Once at the summit of
Mynydd Cil Cwm two points were surveyed with the Trimble, the first where we
judged the high point of the hill to be situated and the second where the 527m
spot height on Ordnance Survey maps appears on the ground.
Gathering data at the first of two positions on the summit area of Mynydd Cil Cwm |
Gathering data at the second of two positions on the summit of Mynydd Cil Cwm |
As the last of the two
lots of 300 data points were collected I switched the machine off, took a few
photos and we retraced our steps down toward the hill’s bwlch. This now has a conifer plantation on its
eastern side, which is not shown on my old 1:25,000 Explorer map. The bwlch spot height that appears on the
enlarged Geograph map is placed at a meeting of fences, we judged the ground to
the north-east of the fence junction to be lower on the hill to hill traverse
and I placed the Trimble on top of my rucksack to give it elevation above the
ground and set it to gather more data.
By now Aled had descended to the track which wound its way down the
northern slopes toward our next hill as this part of land was infested with
flying ants, which I didn’t particularly mind until one bit me.
Gathering data at the critical bwlch of Mynydd Cil Cwm |
We now lost height
heading toward Bryn y Fedwen, this hill is listed as a Pedwar with 32m of drop
based on a basic levelling survey conducted on 16.10.03, and it is also given
the same 32m of drop on Ordnance Survey maps with a 373m spot height appearing
on the Ordnance Survey enlarged map on the Geograph website. However, before Trimbling the summit and
critical bwlch of Bryn y Fedwen, the next connecting bwlch was that of Moelfre,
and this was the next point to survey.
As we made our way down
to the critical bwlch of Moelfre the land to our south-west slipped into
connecting steams all rising to the eloquent shaped Foel Fadian, which is
another Uchaf overlooking carved out plunging northern land. Further north Moelfre and Llannerch yr Aur
gave a foretaste of our continuing route, with the former defaced on its upper
southern slopes by felled forestry, whilst the latter was a mass of purple as
heather and its association with wilderness predominated.
The elegant profile of Foel Fadian |
The purple hillsides of Llannerch yr Aur |
The next critical bwlch
was situated in a large sheep pen which took up all of the area of the bwlch
with its connecting pens and fenced off areas.
As the Trimble gathered its allotted data Aled waited patiently beside a
gate and I jotted down the details of the survey, noting the time, number of
satellites the Trimble had logged onto, name of hill, the position of the
survey – be it a summit or a bwlch, the measurement offset which in this
instance was 0.41m as the Trimble had been placed on the top of my rucksack
which made a convenient and improvised substitute for a tripod, the feature
where the equipment was placed – in this instance gravel / grass in large sheep
pen, how many data points gathered which is usually 300, duration of survey
which is usually five minutes and lastly the estimated margin of uncertainly
associated with the height placement, in this instance I estimated 0.1m. All of this is scribbled as quickly as
possible and sometimes gives little chance to take in and fully appreciate ones
surroundings.
The sheep penned critical bwlch of Moelfre with Bryn y Fedwen beyond |
Above the sheep pens the
greened summit of Bryn y Fedwen stood out and was attractively set against a
foreground of bright yellowed gorse. By
now the sun was forever sinking in the western sky and we knew that we would be
chasing daylight toward the end of the planned hills and their surveys. But to be out on the hill when daylight turns
to dusk and the sun ebbs its last is a wonderful experience and with my car
parked relatively high and a fence to follow down to it from our last hill, we
knew that although darkness may overtake us we would be safe for the descent.
The greens and yellows of Bryn y Fedwen |
Gathering data at the bwlch of Moelfre |
Once the Trimble was
packed away we headed up to our next summit which is easily identified, within
a couple of minutes the Trimble was set aligned with the high point of Bryn y
Fedwen and gathering the customary five minutes of data. This hill is unusual as it connects two
distinct small land masses which have steep steam vallied northern and southern
slopes, it seems almost island like, squeezed into its small domain and
dominated by its higher neighbours. This
unusual aspect gives it charm and its slopes give easy access to the higher
hills to its north and south, and it was the northern land we now continued
toward, but our next survey was only a few hundred metres away at the
connecting bwlch to Moelfre, which was our next hill. The connecting bwlch is placed on a gravelled
track and we took two data sets from it, one either side of a gate.
Heading toward the summit of Bryn y Fedwen |
Aled at the summit of Bryn y Fedwen |
Gathering data at the summit of Bryn y Fedwen |
Gathering data at the bwlch of Bryn y Fedwen |
Our onward route
followed a forest track for a short distance before we branched off on a green
track as it wound its way steeply up the southern slopes of Moelfre. This hill dominates this northern part of our
route and its summit area is small and flattish, when we arrived I tried to
regain my breath and assembled the Trimble as quickly as possible as we still
had two hills to visit and quite a distance to cover.
Gathering data at the summit of Moelfre |
Up until now the
majority of this walk had been on high re-claimed land now given over to sheep
grazing with closely cropped grass amongst longer breeze blown grass, with only
the summit of Mynydd Cil Cwm still retaining its wild element of heather, but
all this was to change as the next hill on our route was shining purple ahead
of us with copious amounts of heather on display. This hill is Llannerch yr Aur and it is
another that I had surveyed with my old wooden staff with a 34.7m drop value
attained, however the accuracy of this survey is questionable as the territory
it was conducted on is not conducive for such things, my surveying notes of the
day give the following detail ‘measured from a small puddle at the south-western
end of bwlch, this hill is all heather and is another fine little addition’, this
sentiment is as applicable today as in October 2003 from the hill first entered
the ranks of hills now known as Y Pedwarau.
Llannerch yr Aur - resplendent in its purple haze |
As we descended toward
the bwlch the heather proved a delight to walk through as it was soft and
formed a relatively flat under surface with clouds of dust pollen rising as we
continued through it. What proved
bothersome were the grass tussocks which formed next to wetter areas, once at
the area of the bwlch a fence marched across it in a south-west to north-east
direction, we couldn’t linger as the sun was forever getting lower in the sky
and once the land was assessed the Trimble was placed on top of my rucksack and
data gathered. This position proved to
be beside the same puddle that I had surveyed from, 12 years ago.
Heading toward Llannerch yr Aur |
Gathering data at the critical bwlch of Llannerch yr Aur |
By now the day’s
exertions were beginning to take their toll and as we made our way up toward
the summit of Llannerch yr Aur, Aled went ahead and at every rise he then
continued, as I was behind him I hoped that the next rise would prove to be the
high point but there were at least three false summits, but as with every hill
the true summit is eventually reached.
This particular hill has two distinct possibilities for its high point,
before setting the Trimble up we both judged their merits and both decided that
the furthest one from the direction that we had approached from, looked the
higher.
As I placed the Trimble
on my rucksack at the summit Aled went to the edge of steep ground that looked
out to our south and east and he beckoned me to join him, I waited until the
file had been created in the Trimble and it was set to achieve its 0.1m
accuracy before data should be logged, before venturing down to join him, and
the view when I got there was sublime and accentuated by the low light and the
purple haze of heather with dulled sun afterglow on distant hills. I stood and looked at this scene and only
interrupted my gaze to press ‘Log’ before re-joining Aled. The land plunged down below us into gathering
shade with the ebbs of the evening sun now just highlighting immediate land and
far off hill tops. We could not linger
as we still had at least two surveys to conduct.
Admiring the view |
Gathering data at the summit of Llannerch yr Aur |
The view south-west from the summit of Llannerch yr Aur |
Leaving the summit of Llannerch
yr Aur we headed back toward its bwlch and then gained ground whilst contouring
north toward a small pool that feeds water into Llynnau Caeconroi, which I had
walked past on my only previous visit to these hills.
On our way toward Banc Bron Derwgoed |
Dusk was quickly
overtaking us as the sun had now dipped behind the intervening hillside, but as
we walked down steep ground and over the stream feeding from the high pool and
up the other side we came back out into the last remnants of light. This stream is placed in a rather beautiful place
with hillsides of gorse and fern that had dimmed in the evening light adding
gentleness to the framed view of our last hill of the day; Banc Bron Derwgoed.
Heather, gorse and fern dimmed in the evening light with Banc Bron Derwgoed beyond |
Llynnau Caeconroi |
By the time we had
gained the track on the ridge that leads down to the bwlch of Banc Bron Derwgoed
the sun was aglow in the western sky with its orange orb quickly disappearing
from view, we had enough time to take a number of photos before pressing on to
the hill’s critical bwlch. We now knew
that dusk and possibly darkness would overtake us so we assessed the lay of
land at the critical bwlch and judged where the Trimble should be placed and
then continued to the summit.
Daylight quickly disappeared as we approached the bwlch and summit of Banc Bron Derwgoed |
As darkness approached we still had four surveys to conduct |
Banc Bron Derwgoed is
another interesting hill for those who immerse themselves in numerical data as
it is listed as a Pedwarau with 30m of drop based on a 30.2m basic levelling
survey conducted on the same day as those for Llannerch yr Aur and Bryn y
Fedwen, but it is not listed in the Tumps as I suspect that that listing relies
upon current Ordnance Survey data for its exclusion. The Ordnance Survey map data gives a drop
value of 28m for this hill based on a 404m summit spot height and a 376m bwlch
spot height.
When we got to the
summit and started assessing the land we knew it would be dark before we left
as there are three distinct possibilities for the high point of this hill, with
a fourth point also considered but visually dismissed. Each of the three points was Trimbled, and
very quickly the last ebbs of light that were still with us when we had arrived
on the summit were now disappearing and by the time that the third potential
summit survey was taking place the whole land had turned dark and only
silhouettes of distant hills could be glimpsed.
Gathering data at the first of three surveys conducted at the summit area of Banc Bron Derwgoed |
Once the third survey
was complete at the area of the summit I packed the Trimble away and we retraced
our route back toward an area of intervening gorse, we tackled this from a
different approach compared to our ascent, and thankfully this proved easier,
beyond this we kept beside the ridge fence which led us back down to the
connecting bwlch and the last of fourteen surveys for the day. Having assessed the bwlch on our ascent we
knew where the Trimble should be placed and within a few minutes it was set up
gathering data.
Gathering data at the critical bwlch of Banc Bron Derwgoed, the last of fourteen surveys for the day |
All that remained was a
wander down dark hillsides beside a fence and back to my car. The walk had taken us 6 hours 25 minutes with
much of this time being taken up with the fourteen surveys. The hills on route are recommended as they
are seldom visited and give a perspective to the Pumlumon range lacking from
their higher and more popular counterparts.
Survey Result:
Bryn y Fedwen
Summit Height: 404.8m (converted to OSGM15) (Pedwar status confirmed)
Summit Grid Reference: SN 85170 97211
Bwlch Height: 373.3m (converted to OSGM15)
Bwlch Grid Reference: SN 85111 97555
Drop: 31.5m (Pedwar status confirmed)
Dominance: 7.79%
Dominance: 7.79%
Moelfre
Summit Height: 468.1m (converted to OSGM15)
Summit Grid Reference: SN 84818 98354
Bwlch Height: 362.4m (LIDAR)
Bwlch Grid Reference: SN 84990 96904 (LIDAR)
Drop: 105.7m (Trimble summit and LIDAR bwlch)
Dominance: 22.58% (Trimble summit and LIDAR bwlch)
Dominance: 22.58% (Trimble summit and LIDAR bwlch)
Llannerch yr Aur
Summit Height: 437.4m (converted to OSGM15)
Summit Grid Reference: SN 86309 97855
Bwlch Height: 403.3m (converted to OSGM15)
Bwlch Grid Reference: SN 85962 98078
Drop: 34.0m (Pedwar status confirmed)
Dominance: 7.78%
Dominance: 7.78%
Banc Bron Derwgoed
Summit Height: 404.2m (converted to OSGM15)
Summit Grid Reference: SN 87154 98796 (summit relocation confirmed)
Bwlch Height: 376.4m (converted to OSGM15)
Bwlch Grid Reference: SN 86863 98871
For further details please
consult the Trimble survey spreadsheet click {here}
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