Mapping Mountains – Trimble Surveys – Aran and Y Berwyn

 

24.04.21  Braich yr Hwch (SH 877 233), Foel Hafod Fynydd (SH 877 227), Esgeiriau Gwynion (SH 889 236), Foel Rudd (SH 895 239) and Ffridd Cwm Ffynnon (SH 891 250) 

Braich yr Hwch (SH 877 233)

The high Aran are impressive hills.  From the east their profile always stands out.  Dominating this range of hills is Aran Fawddwy, which south of Yr Wyddfa is the highest point in Britain.  When I first started hill walking the Aran drew me in along with Cadair Idris and the higher Eryri peaks to their north.  But it was the Aran that I favoured, partly no doubt as they are relatively close to where I live, but convenience was not all.  At this time few paths existed between many of this ranges hills and their northerly territory only had access via a courtesy path.  This was many years before the open access that we now enjoy today.  This partly forbidden territory only added to their appeal as a courtesy path can soon be turned in to investigation farther afield. 

This was many years ago, and now my walking is more contemplative and having visited the higher hills of Wales so many times I now enjoy investigating other hills, many of which are much lower in height, but nonetheless still situated in beautiful landscape.  However, opportunity to visit the higher hills still occasionally takes place and today a route had been planned taking in Ffridd Cwm Ffynnon as a marginal non-Dewey and Braich yr Hwch as a P10 needing to be surveyed, between the two are Foel Hafod Fynydd, Esgeiriau Gwynion and Foel Rudd.  This circuit gave good bagging and surveying potential.  It also gave stunning views in to those higher Aran hills with the block of cliffs between Aran Fawddwy and Aran Benllyn only broken by the steep grassed slope leading to Erw y Ddafad Ddu. 

The high Aran

I met Aled in the Llanuwchllyn car park and he then drove further up valley to our designated parking place, with Mark later joining us on the hill.  From here we walked up Cwm Croes with me taking great delight pointing out all the potential parking places that we had disappointedly ignored! 

The forecast for the day was good with clear skies, but with a chilled easterly breeze.  After leaving the car the high Aran was already on grand display with their cliffs dominating above the foreground of green pastured grazing fields; a stunning sight to greet us as we set off on our walk.  As our meeting time was all too uncivilized for Mark, he was setting off an hour or so later and would meet us on the hill. 

Erw y Ddafad Ddu

The paved road up Cwm Croes ends at Nant-y-barcut farm, from here a good track continues toward the buildings of Cwm-ffynnon which are undergoing renovation.  A vehicle track on the moor then heads up toward Cwm Ddu with a path continuing to Bwlch Sirddyn where we would meet Mark in a few hours’ time.  We opted to follow the vehicle track toward the bottom of steep ground that led up Braich yr Hwch; the P10 that Aled wanted surveying. 

The steepness soon increased and my pace relented to a steady gasping plod.  However, to compensate the view opened up and what a view it was.  The cliffs of Erw y Ddafad Ddu are rarely seen than from this vantage point, whereas those of Aran Fawddwy and Aran Benllyn always stand out.  But this route gave us such a close view in to the steep rising ground up to the main Aran ridge. 

The cliffs of Erw y Ddafad Ddu

The track on the moor that we followed turned out to be made by a quad bike and this kept to the rising ground as it tapered in to a narrow steep ridge, not a place that I would favour riding such a thing, a skilled hand would be needed to negotiate safe passage. 

Heading toward the steepening slopes of Braich yr Hwch

Eventually I crested the upper ridge and Aled was standing on the high point of Braich yr Hwch.  I soon set the Trimble up to gather its allotted data.  Once the equipment was closed down and packed away we headed down to the hill’s connecting bwlch where we spent a few minutes assessing the lay of land before choosing placement for the Trimble. 

Nearing the summit of Braich yr Hwch

Gathering data at the summit of Braich yr Hwch

As I sat scribbling all necessary details in my survey notebook, Aled called over as he had spotted Mark walking up the valley.  Once bwlch data were gathered and stored we made our way up continuing steep ground toward the summit of Foel Hafod Fynydd.  Thankfully the steepness relented toward the upper part of the hill, but I still needed to gather my breath once at the summit. 

Gathering data at the bwlch of Braich yr Hwch

Aran Fawddwy from near the summit of Foel Hafod Fynydd

The high point of Foel Hafod Fynydd is positioned a few metres from its cairn and soon the Trimble was placed on Aled’s rucksack with its internal antenna aligned with the high point of the hill and once the 0.1m accuracy level was attained before data should be logged, I set it to gather data and joined Aled sitting below the equipment and out of the brisk breeze. 

Gathering data at the summit of Foel Hafod Fynydd

The next point to survey was the bwlch connecting Foel Hafod Fynydd with Esgeiriau Gwynion.  To get to it involved losing a lot of height on very steep ground.  As we contoured around the upper part of the hill I spotted a figure sheltering behind a peat hag down at the bwlch; it was Mark.  Arriving at the bwlch it was good to see him.  He had spotted us making progress toward the summit of Foel Hafod Fynydd and had been waiting at the bwlch for about 45 minutes. 

Descending steep ground toward Bwlch Sirddyn

For some perverse reason I had always wanted to survey this bwlch.  I think this is due to contrasting contour information on contemporary Ordnance Survey and Harvey Maps as well as the old 5m contouring that was available on the OS Maps website.  Prior to this survey this bwlch was listed with an estimated c 500m height and now it was time to put an accurate height to it. 

Erw y Ddafad Ddu and Aran Benllyn from Bwlch Sirddyn

We each gave an opinion toward the position of the bwlch and agreed that it was ground beside the fence that crosses the land on the hill to hill direction.  The Trimble was soon positioned on one of the fence posts and gathering data. 

Gathering data at the bwlch of Esgeiriau Gwynion

During data collection I sat with Mark and Aled out of the breeze behind a peat hag listening to their conversation whilst enjoying a sandwich, all seemed good in the world!  I left the Trimble to collect 10 minutes of data before closing it down, packing it away and then looking up at the steep rising ground ahead.  This led to the summit of Esgeiriau Gwynion and as I ever so slowly plodded up the slope and emerged near the top of this horrendous slope, I looked at Mark and said that ascending it was like being tortured by the Spanish inquisition. 

Steep ground leading up toward the summit of Esgeiriau Gwynion

Mark is close to the high point of Esgeiriau Gwynion as surveyed by the Trimble GeoXH 6000

Two points were surveyed for summit position of Esgeiriau Gwynion.  The first which many believe to be the high point is beside a small cairn of quartz rocks which has a discarded old fence post stuck in the middle of it.  The second point was beside the ridge path adjacent to a fence that we had followed to make our way to the cairn, whilst doing so we all commented that we thought ground beside this fence higher than that beside the small cairn.  We’ll have to wait for the Trimble data to be processed before this question is answered. 

The first of two positions surveyed for the summit of Esgeiriau Gwynion

These two surveys also gave me time to sit and rest and soak in that ever present and wonderful view.  The breeze still blew, but the chill of early morning was being quickly replaced by an afternoon warmth, all too welcome on the higher hills. 

The second of two positions surveyed for the summit of Esgeiriau Gwynion

We had two further hills to visit and survey, but thankfully the majority of the uphill was now behind us.  Leaving the summit area of Esgeiriau Gwynion lay large peat hags, all dry and all looking other worldly with their parched moor grass not yet summer greened.  Beyond these lay a descending moor leading down to the connecting bwlch with Foel Rudd. 

Heading toward Foel Rudd

Although relatively expansive the position of the critical bwlch of Foel Rudd was not difficult to pinpoint.  With direction from Mark and Aled I headed toward where we considered it lay, whilst doing so I walked up a part of the southerly valley following a narrow channel which led me to where I then placed the Trimble. 

Gathering data at the bwlch of Foel Rudd

Once the allotted bwlch data for Foel Rudd was gathered and stored we followed a narrow path up to the hill’s summit.  We all agreed that the high point was amongst heather approximately 2 metres from the small quartz cairn and fence post that adorns the hill. 

Gathering data at the summit of Foel Rudd

The Trimble set-up position at the summit of Foel Rudd

Just one hill remained; Ffridd Cwm Ffynnon, which is positioned on the northerly descending ridge from Esgeiriau Gwynion.  I had visited this hill once before in May 2002 with Bill Owens who had helped me with a basic levelling survey of the hill. 

We started to descend from the bwlch connecting with Foel Rudd, with the ground soon turning in to the roughest experienced during the day.  The rough stuff mainly consisted of reed grass and some bog, it was never difficult but toward the end of many hours on the hill it sapped my already depleting stores of energy. 

The last hill of the day; Ffridd Cwm Ffynnon

A raised embankment crosses the bwlch of Ffridd Cwm Ffynnon and heads toward and beyond its summit.  This is an old field or ffridd boundary and is now grassed over with just an occasional quartz rock protruding from its side.  We debated where to gather data from at the bwlch, having all decided that the embankment was obviously man-made and therefore should be discounted from being taken as a part of either the bwlch or summit height of the hill. 

Having decided upon a suitable position for the bwlch, I placed the Trimble on top of a fence post and with Mark’s help measured the offset between its internal antenna and the ground at its base and then waited for the allotted data to be gathered and stored. 

Gathering data at the bwlch of Ffridd Cwm Ffynnon

A narrow path beside the embankment led us to the summit of Ffridd Cwm Ffynnon and an Abney level was then used to determine on which side of the embankment and adjoining fence the highest remaining natural ground lay.  Once determined, the Trimble was soon set up gathering its tenth and last data set of the day. 

Gathering data at the summit of Ffridd Cwm Ffynnon

All that now remained was to re-trace our route back to the connecting bwlch and follow a track down in to the upper reaches of Cwm Ffynnon.  It was a beautiful route down with the high Aran now no more than blued silhouettes with the afternoon sun hiding their morning’s detail. 

The blued late afternoon silhouette of the high Aran

Descending in to the bowl of the cwm meant that the breeze also now left us and it soon warmed proceedings with the afternoon sun increasing in strength.  It was also a relatively long walk out, back past Nant-y-barcut farm and down the paved lane. 

Farm life on the way through Cwm Croes

Time to rest and enjoy the sunshine

I stopped occasionally to take in the scene and also take a few photos with chickens and lambs highlighted by rich afternoon colour.  It had been another good day on the hill, my third consecutive day which is a rarity for me nowadays.  I arrived back at the awaiting cars a few minutes after Mark and Aled and proceeded to bask in the luxury of getting my walking boots off.  A simple pleasure desperately needed! 

 

Survey Result: 

 

Braich yr Hwch

Summit Height:  576.0m (converted to OSGM15)

Summit Grid Reference:  SH 87754 23371 

Bwlch Height:  567.6m (converted to OSGM15)

Bwlch Grid Reference:  SH 87682 23247

Drop:  8.4m

Dominance:  1.46%

 

 

Foel Hafod Fynydd

Summit Height:  688.1m (converted to OSGM15, Trimble GeoXH 6000)

Summit Grid Reference:  SH 87759 22714 (Trimble GeoXH 6000) 

Bwlch Height:  c 603m (interpolation)

Bwlch Grid Reference:  SH 87018 22664 (interpolation)

Drop:  c 85m (Trimble GeoXH 6000 summit and interpolated bwlch)

Dominance:  12.37% (Trimble GeoXH 6000 summit and interpolated bwlch)

 

 

Esgeiriau Gwynion

Summit Height:  669.6m (converted to OSGM15)

Summit Grid Reference:  SH 88925 23616 

Bwlch Height:  499.6m (converted to OSGM15)

Bwlch Grid Reference:  SH 88466 22985

Drop:  170.0m

Dominance:  25.39%

 

 

Foel Rudd

Summit Height:  657.8m (converted to OSGM15)

Summit Grid Reference:  SH 89563 23949 

Bwlch Height:  639.8m (converted to OSGM15)

Bwlch Grid Reference:  SH 89297 23914

Drop:  18.0m

Dominance:  2.74%

 

 

Ffridd Cwm Ffynnon

Summit Height:  534.2m (converted to OSGM15)

Summit Grid Reference:  SH 89182 25074 

Bwlch Height:  507.0m (converted to OSGM15)

Bwlch Grid Reference:  SH 89143 24686

Drop:  27.2m

Dominance:  5.09%

 

 

For further details please consult the Trimble Survey Spreadsheet

 

 

Mapping Mountains – Trimble Surveys – Aran

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.

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.

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.

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. 

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.

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%

  

For further details please consult the Trimble Survey Spreadsheet

Mapping Mountains – Trimble Surveys – Aran

26.02.18  Tŷ Croes (SH 785 187) and Foel Caerynwch (SH 772 179)

Foel Caerynwch (SH 772 179)

Occasionally in life the hills are there for more than views and enjoyment, they are also there in times of need, when the soul needs replenishing and a mind needs to think and assess, this morning was such a day.

I’d only decided on the morning’s walk late last night, on a whim, out of an inner need to be on the hill.  I knew which hill to head for, one whose rounded top I had viewed from many a direction and yet never visited.  It was a hill that had been on my radar for a number of months and it did not disappoint.

The hill is named Y Foel on Ordnance Survey maps and it is situated mid-way between Dinas Mawddwy and Dolgellau.  When compared to its many higher neighbours it is only small in height and yet for me, there is something special about its shape, as having an elongated upper ridge leading to a grassy coned summit seems to personify many a Welsh hill, I thought it must be seldom visited outside of the farming community with only an occasional hill walker going its way.

I set off from the outskirts of Brithdir to the hill’s north; it was bitingly chilly with winter morning colour enhancing the adjacent higher hills to the north.  It was good to be out, in an environment that I am accustomed to, an environment that over many years has given me so much.  Being on the hill seldom disappoints whatever the weather and whatever the season, the hills enhance and enthral, they are a wonderland difficult to quantify.  They give simple and yet fulfilling pleasure and they help to fathom those intricate ways of life’s complexities.

Winter colour on Rhobell Fawr

The route to the hill took me up a narrow paved road, at the end I veered left on to open but walled hill side, following who I thought to be a farmer, they were in fact a contractor who along with a colleague was rebuilding one of the many stone walls, a cold job for the day as an easterly wind chilled the land.

I stopped and talked with Dewi Thomas; the contractor, who was local to Dolgellau, he gave me two hill names and kindly posed for a photograph.  These meetings with people who work the land, who on the main are from the farming community are a pleasure to have, they have taken place on a frequent basis over recent walks, they enhance the pleasure I get from the hills, and inform and bring local knowledge to an otherwise unknown landscape.

After this chance meeting I made my way to the top of a 307m map heighted bump that the Tithe names as Tŷ Croes and assembled the Trimble aligned with the high point, as it gathered data I stood and took in the colour wash as the winter sun cast rich colour across the higher hill to my west, this is the hill named Y Foel on the map and which Dewi told me is named Foel Caerynwch, a name I noted and hoped to substantiate later in the day.

Gathering data at the summit of Tŷ Croes

Sheep tracks led me to the hill’s connecting bwlch which bisected a vehicle track, I placed the Trimble on top of my rucksack and gathered another data set, during this I stood back and admired the moor, a bleached and yet radiantly delicate golden colour that will turn with the passing of the seasons to a luxuriant emerald green before the brilliance of orange tinged colour vividly strikes the Autumnal land.

Gathering data at the bwlch of Tŷ Croes

By now bulbous snow flurried clouds were massing to the east, but in the main the upper ridge I was now on remained bathed in winter sunshine.  The next point to survey was the critical bwlch of Foel Caerynwch, this proved a wide expanse of bog, which today was thankfully frozen.  I positioned the Trimble to gather data and waited for the allotted 300 datum points to be stored.  After gathering the equipment up and packing it away I continued toward the high point of the day.

Gathering data at the critical bwlch of Foel Caerynwch

Although one aim for the day was to visit new hills, and another to survey and gather data, my underlying need was to think and let my mind open and race and consider and assess and possibly even conclude.  I did much of this during the day, it seemed to help, but sometimes life can be difficult, even complicated and occasionally even after time on the hill the conclusion that is reached is the one that was there before.

The view north-east beyond Tŷ Croes

Cadair Idris and Foel Caerynwch

Approaching the summit of Foel Caerynwch

Reaching the summit of Foel Caerynwch the easterly wind blew across its top with flecks of snow being cast across the land.  It was wondrous to be out on such a day.  I stood in the lee of the wind whilst the Trimble gathered its last data set of the day, occasionally glimpsing the mass of Cadair Idris, a gem of a hill from this direction with its rounded cliff shaped summits soaring skyward.

Gathering data at the summit of Foel Caerynwch

Looking north-west toward Foel Offrwm

I joined a green path on the descent, a lovely way off the hill, and one that took me to Tyn Llidiart where Terry and Marion Ogden were out busying themselves around their car, I stopped and chatted, Marion smiled when telling me that they know the higher of the two hills I had visited as The Pimple, and that its name is Foel Caerynwch, and asked if I had noticed this name on one of the wooden marker posts just back up the path, I hadn’t and was intrigued, so double backed finding a Snowdonia National Park information board, a finger post and wooden marker post all giving the hill’s name as Foel Caerynwch.

And the name of the hill is.........

It had been a chance encounter with Marion and Terry, but one that led me to the name of the hill being substantiated by another local and by the National Park via their information board, finger post and marker post.  I had missed all these when walking down the green track; my mind had wandered to other things, ones whose importance was a part of my day on the hill.  Walking back to my car I thought how a mind can be a delicate and complicated thing, missing detail that is on show whilst still immersed in thought.

Survey Result:

Tŷ Croes (significant name change)

Summit Height:  306.6m (converted to OSGM15, Trimble GeoXH 6000)

Summit Grid Reference:  SH 78563 18733 (Trimble GeoXH 6000)

Bwlch Height:  288.95m (LIDAR)

Bwlch Grid Reference:  SH 78671 18487 (LIDAR)

Drop:  17.7m (Trimble GeoXH 6000 summit and LIDAR bwlch)

Dominance:  5.77% (Trimble GeoXH 6000 and LIDAR bwlch)

Foel Caerynwch (significant name change)

Summit Height:  342.9m (converted to OSGM15)

Summit Grid Reference:  SH 77261 17997

Bwlch Height:  304.0m (converted to OSGM15)

Bwlch Grid Reference:  SH 78442 18047

Drop:  38.9m

Dominance:  11.35%

For further details please consult the Trimble Survey Spreadsheet