Friday 2 July 2021

Mapping Mountains – Trimble Surveys – Beacon Hill


23.04.21  Two Tumps (SO 117 850), Bryn Coch (SO 124 848), Cilfaesty (SO 128 840) and Banc Gorddwr (SO 111 835) 

Cilfaesty (SO 128 840)

Having visited six hills around and including Beacon Hill yesterday and with the glorious April weather continuing, I wanted to visit Bryn Coch and Cilfaesty, two hills that are relatively close to where I live and which I had only visited on two previous occasions, the last of which was in May 2013.  These hills are positioned to the north of Beacon Hill and with the prospect of visiting and surveying Two Tumps and Banc Gorddwr; two lower heighted hills joined to their higher counterparts and with the bwlch of Cilfaesty also added to the day’s surveying agenda, it promised to be a good day on the hill and would complete the numerical gap for the hills taking in Cilfaesty and Beacon Hill. 

The first survey of the day was beside the high point of the B4355 road as it makes its way over the moor from Dolfor in the north toward Beguildy in the south-east.  This was one of two potential bwlch positions for Banc Gorddwr, which is classified as a 400m Sub-Pedwar and which rose above the road looking across it to the higher hills of Bryn Coch and Cilfaesty. 

I’m always wary of where the Trimble is positioned during a survey on or beside a road, but during data collection only one car passed and after the allotted data were gathered and stored I left the road and headed on a gravelled track and then pastored grazing fields toward the second potential bwlch position for Banc Gorddwr. 

Gathering data at the first of two positions surveyed for the bwlch of Banc Gorddwr

The weather conditions were similar to yesterdays with blue sky dominating and a chilled breeze blowing across the land.  By the time I reached the second potential bwlch a farm vehicle came down an adjacent field from the direction of Two Tumps.  It was soon driving across the same field I was now in but on the opposite side of a large area of reed grass which signified the low point of the land on the valley to valley traverse.  It zoomed off to a lower part of the field gathering sheep as it did so.  It later came back up the field close to where I was standing assessing the lay of land; I waved across and walked toward it. 

Early morning heading toward Bryn Coch and Cilfaesty

The vehicle stopped and I explained what I hoped to do, and asked about the name of the hills and we chatted for ten minutes or so.  The farmer told me where the drainage point was on the field, and I joked and asked him if I could employ him as a surveying assistant, we both laughed when he enquired what the pay would be like. 

Before leaving I asked if I could use the gate that he had driven through for access to the summit of Two Tumps, and having said yes and telling me how good the view was from the summit he left with a wave and a smile. 

I proceeded to gather data from the point where he had directed me to for the drainage of the bwlch and afterward continued up to the summit of Two Tumps.  This hill, as the farmer had told me, has a stunning and expansive view.  Some views can be dramatic and especially so when confronted by either cliffs or sheer drops, others are pleasing to the eye where ridges cascade in to the distance, whereas the view from the summit of Two Tumps is neither, it is just extensive, but when you have Cadair Idris and the Aran as major mountain ranges shooting skyward way off in the distance as well as a myriad of other hills on show it proved a wonderful view to savour. 

Gathering data at the second of two positions surveyed for the bwlch of Banc Gorddwr

I gathered data from three different positions for the high point of Two Tumps with my favoured position being the top of one of the two tumuli that give the hill its name.  Afterward I walked down to its connecting bwlch to also gather data.  This bwlch is where the reclaimed pastored grazing land butts up against the moorland of Bryn Coch and Cilfaesty and once bwlch data were gathered and stored; I then headed up to the summit of Bryn Coch. 

Gathering data at the summit of Two Tumps

Gathering data at one of the positions surveyed for the summit of Two Tumps

Gathering data at the bwlch of Two Tumps

The summit of Bryn Coch consists of moor grass and large amounts of heather and the high point was relatively easy to determine.  As the Trimble beeped away gathering data I stood back and admired the view and also looked to my south where the connecting bwlch between this hill and the higher Cilfaesty lay hidden.  I had no memory of this bwlch from my previous visits so did not know how unsavoury its undergrowth was.  It proved a delight to get to and walk over and also survey as a vehicle track on closely cropped grass heads directly over the bwlch and continues up the northern flank of Cilfaesty.  I’d spotted the same track on the western fringe of Bryn Coch and wondered how far on the moor it went.  Once on it, it took me up toward the summit of Cilfaesty, back down to the bwlch and then onward back toward the summit of Two Tumps, but before this I had to survey the bwlch of Bryn Coch. 

Gathering data at the summit of Bryn Coch

The Trimble set-up position at the summit of Bryn Coch

Positioning the Trimble atop my rucksack on the dried earthen track I stood an appropriate distance away from it as it gathered data, so as not to get in the way of satellite reception and waited until the allotted data were stored.  Surveys are now the norm for me on a hill, although during the recent winter lockdown I did many local walks either up Yr Allt or Y Golfa where the Trimble was left at home as both summits had been previously surveyed.  However, in the main doing a hill walk without the Trimble and prospect of surveying is now a rarity.  Surveying certainly breaks the rhythm of a hill walk, something that I was not fully conscious of before investing in the equipment, but it does give time to look and reflect, more so when operating the Leica equipment when a minimum of an hour of gathered data was the norm whilst surveying with John Barnard and Graham Jackson.  Whereas the Trimble only requires two minutes of data collection to produce an accurate result, I usually push the proverbial boat out and gather five, but even this relatively short period of time gives opportunity to stop, listen and look, just to slow down ones aims and savour those moments in the beautiful uplands that Wales has to offer. 

Cilfaesty from the approach to the connecting bwlch with Bryn Coch

Gathering data at the bwlch of Bryn Coch

The summit of Cilfaesty comprises discarded debris consisting of wind torn black bin liners and once there I soon had the Trimble set up gathering data.  During data collection I watched as two horses appeared to my west, they each stopped to drink from a small pool just out of view.  One spotted me and stood proudly looking directly at me.  I watched each as I left the summit, with both slowly becoming ever smaller silhouettes against a radiant blue sky. 

Gathering data at the summit of Cilfaesty

I've been spotted!

Heading back over the bwlch I continued up the green track which soon brought me to the fence which to my east continued up the short distance to the connecting bwlch for Two Tumps.  The track now continued as no more than vehicle marks on the pastored grazing field.  It led me back to a gate close to the summit tumuli of Two Tumps and then down toward the second reedy bwlch position I had surveyed earlier in the day.  From here it was only a short distance back to my car. 

I now wanted to visit and survey the summit of Banc Gorddwr whose bwlch I had surveyed earlier in the morning.  Therefore, I re-positioned my car further up the minor road that leaves the B4355 and parked where a track veers off the tarmac across one of the adjacent fields.  The ground was so dry that I could have parked anywhere on the near field. 

An easy walk to the summit of Banc Gorddwr

A narrow path led from the minor road up over the moor to the summit of Banc Gorddwr which as I approached looked as if it was crowned by an attractive rock.  This ‘rock’ is grey, weathered and has moss growing on it but upon further investigation it proved to be hollow and if placed there as an imitation rock it almost convinced me.  I placed the Trimble approximately 2 metres from it and gathered the last summit data set of the day. 

Gathering data at the summit of Banc Gorddwr

Once back at my car I drove the short distance toward Waen farm and parked on the grass verge and walked down the lane to where I now wanted to survey two points for the critical bwlch position of Cilfaesty.  The first of which was either on or beside the track leading to the farm.  As I walked down the track a quad bike drove up it.  I chatted with Charles Jones for ten minutes or so, explaining where I’d just been, my interest in surveying and hill names and the importance of his track and land near it. 

Charles Jones

Charles was extremely co-operative considering someone had just turned up asking if they could clamber over a fence into the adjacent field to sit on grass for ten minutes whilst a small piece of equipment positioned on a rucksack quietly beeped away, and he had no problem whatsoever with me wandering around the field assessing the lay of land. 

I took two data sets for the bwlch position of Cilfaesty, the first from where I judged the highest remaining natural ground was positioned adjacent to the track, this was obviously higher bur also man-made and similar in appearance to an under filled land bridge and therefore as such discounted from the height of the bwlch, and the second position from a slender and steep connection of land overlooking a picturesque small pool. 

The first survey took an inordinate amount of time for the Trimble to attain the 0.1m accuracy level before data should be logged, but I was in no rush as I had permission to sit in the field and the sun was out and that chilled breeze from early morning was now no more than a remnant of memory. 

Gathering data at the first of two positions surveyed for the bwlch of Cilfaesty

After the first of these last two data sets of the day was safely gathered and stored I clambered back over the fence, went through the opposing open gate and walked past a small bowl of land which is now used as a rubbish heap to where the second potential bwlch position is placed.  This position overlooks a small pool with steep brackened slopes dotted with badger sets and a view out toward Cilfaesty, it is an attractive position for a potential bwlch to be placed.  Unfortunately a few metres from it was a discarded wheelie bin and across the near fence and at utter contrast to it was the rubbish heap, however it was still a wonderful site even with the accompaniment of the wheelie bin! 

Gathering data at the second of two positions surveyed for the bwlch of Cilfaesty

Again it took a lengthy period of time for the Trimble to attain the 0.1m accuracy level, but once it had I pressed ‘Log’ and sat contentedly waiting for the allotted data to be gathered and stored before heading back to the minor lane and my awaiting car. 

 

Survey Result: 

 

Two Tumps

Summit Height:  507.7m (converted to OSGM15)

Summit Grid Reference:  SO 11778 85096 

Bwlch Height:  499.4m (converted to OSGM15)

Bwlch Grid Reference:  SO 12321 84963

Drop:  8.3m

Dominance:  1.63%


 

 

Bryn Coch

Summit Height:  519.1m (converted to OSGM15)

Summit Grid Reference:  SO 12497 84866 

Bwlch Height:  481.9m (converted to OSGM15)

Bwlch Grid Reference:  SO 12594 84370

Drop:  37.3m

Dominance:  7.18%


 

 

Cilfaesty

Summit Height:  527.8m (converted to OSGM15)

Summit Grid Reference:  SO 12803 84079 

Bwlch Height:  385.2m (converted to OSGM15)

Bwlch Grid Reference:  SO 12044 82276

Drop:  142.5m

Dominance:  27.01%


 

 

Banc Gorddwr

Summit Height:  488.5m (converted to OSGM15)

Summit Grid Reference:  SO 11192 83538 

Bwlch Height:  466.6m (converted to OSGM15)

Bwlch Grid Reference:  SO 11038 83998

Drop:  21.9m

Dominance:  4.49%


 

 

For further details please consult the Trimble Survey Spreadsheet

 

  

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