Mapping Mountains – Trimble Surveys – Tarennydd

14.05.18  Foel (SH 632 045), Foel Cocyn (SH 624 042), Foel Tyddyn y Berllan (SH 634 051), Gamallt (SH 665 067), Coed Uchaf (SH 649 055), Castell (SH 655 061), Pt. 230.2m (SH 648 063), Craig yr Aderyn (SH 647 065) and Craig yr Aderyn (SH 643 068)

Craig yr Aderyn with Cadair Idris as backdrop

Rising above and to the south of the flat bedded Dyffryn Dysynni is a small land mass enclosing a number of individual hills, this land is topographically adjoined to the Tarennydd, although on first view it extends from land adjoined to the hills of Cadair Idris, with it only being separated by the Afon Dysynni.

I’d contemplated visiting these hills for a number of years, but other hills (as they are prone) had got in the way.  However, after producing a number of accurate heights for both summit and bwlch for these hills via LIDAR analysis I thought it time that I visited, and with the weather set fine I set off for Dolgoch; a small community on the southern side of these hills.

I knew from LIDAR analysis that two of the eight hills I planned on visiting were additions to the Welsh 200m P30 list, and gathering data with the Trimble would no doubt confirm this.

One of the new Welsh P30s - Foel Tyddyn y Berllan (SH 634 051)

A short walk on the B road brought me to the lower part of the first hill’s eastern ridge (the hill is known locally by the farmer who grazes this land as Foel), this climbed steadily upward bathed in the early morning’s sunshine with an old fence following the ridge line and scattered sheep and their lambs contentedly grazing.

The other new Welsh P30 - Foel (SH 632 045)

As height was gained the view opened, and to the north-east Cadair Idris rose highlighted in sunshine with an unadulterated backdrop of delicate blue, the foreground was framed by the hills I planned on visiting and surveying, one led to another, and all looked inviting.

Cadair Idris

Light and shade were accentuated subtleties in shape and profile with the hills of Craig yr Aderyn always drawing the eye, however nestled below this backdrop was the second new P30, this is known locally as Foel Tyddyn y Berllan and its new status awaited confirmation by the Trimble GeoXH 6000.

Foel Tyddyn y Berllan in shade with Craig yr Aderyn in the background

The summit of Foel consists of ground at the base of the ridge fence and within a few minutes of arriving at the high point, the Trimble was positioned on top of a fence post and the measurement offset taken from its internal antenna to the ground below.

Gathering data at the summit of Foel

My second of eight hills on this walk was also the highest and although named as Ffridd Cocyn on Ordnance Survey maps it is known locally by the farmers who I spoke to as Foel Cocyn, although I was surprised with this name it makes sense as a ffridd would apply to an enclosed field and not the whole hill, whilst the term foel would apply to the latter.

Foel Cocyn (SH 624 042)

On my way to Foel Cocyn was the connecting and critical bwlch for Foel, this proved to be positioned in thick grass that merged with a section of reed grass, one shined green in the sun, whilst the other swayed delicately in the morning’s breeze.

Gathering data at the critical bwlch of Foel

A path led up the eastern slopes of Foel Cocyn but I diverted from it when I saw a quad bike heading up toward me from the north, Edward Cook was out with a colleague and two sheep dogs and we talked for a number of minutes, he was the first farmer that gave me the name of Foel Cocyn for the hill explaining that the word cocyn refers to the small hummocks on the hill’s western slopes.

Edward Cook and colleague

After a well-earned rest during which the Trimble gathered its allotted data from the summit of Foel Cocyn, I backtracked toward Foel and continued down from its connecting bwlch heading northward to the bwlch connecting it with Foel Tyddyn y Berllan.

Gathering data at the summit of Foel Cocyn

Foel Tyddyn y Berllan and Craig yr Aderyn

After the bwlch survey I headed to the summit which has a small and attractive rock outcrop as its high point.  As the Trimble gathered data I stood and looked north-eastward toward Craig yr Aderyn, a marvellous view bathed in crisp morning light with the constant backdrop of the iconic Cadair Idris adding height and depth to the scene.

Gathering data at the summit of Foel Tyddyn y Berllan

Castell and Coed Uchaf from Foel Tyddyn y Berllan

By now the day’s warmth was increasing in intensity and the route down toward the outskirts of the small community of Abertrinant was eased with an earthen track leading to the farm of Llanerch-goediog, where I met Stephen Jones whose hills I had just visited and who gave me the name of Foel and Foel Tyddyn y Berllan, explaining that Foel Wyllt, which is a name appearing near these hills on contemporary Ordnance Survey maps, takes in the whole mountain, as in the whole land mass extending south-westward above his farm.

Stephen Jones

After noting the names Stephen gave, I explained about the Trimble and asked if he minded me visiting the adjacent field to survey the critical bwlch of Gamallt, which is a prominent hill to the north-east and one whose summit would have to wait for another day.  Stephen directed me toward the bwlch, telling me to cross the fence that he said was not barbed and then directed me through the field to a gate and my onward route to the next hill, which is known locally as Coed Uchaf.

The critical bwlch of Gamallt was beside a small land bridge and stream at the base of the fence.  It was an attractive spot to shelter under a large tree out of the sun as the allotted data were gathered.  By now the sky was an intense darkened blue, the heat clear and thankfully not oppressive and although the day was warming up it was a delight to be out on the hill.

Gathering data at the critical bwlch of Gamallt

I followed Stephen’s direction from the bwlch and headed toward the gate which gave access to another field and a route toward the summit of Coed Uchaf, it was a steady plod to its high point and whilst slowly making progress a quad bike buzzed around adjacent land, and as the Trimble gathered summit data it arrived close to the top, I waved and headed over to talk with Joanne Redman who was out taking photos of her father’s farm in the valley below.

Wales' two new P30s; Foel (on left) and Foel Tyddyn y Berllan (on right)

Joanne Redman

Joanne recommended I should contact her father; Tomos and kindly gave me his telephone number, I phoned him the next day and also visited him the following week, Joanne told me that the hill we were on is known as Coed Uchaf and is a part of their land, this was also a name that Stephen Jones had used for this hill, with the name being taken from the high wood just to the south-east of the summit, this shone emerald like with summer’s fresh growth.

Gathering data at the summit of Coed Uchaf

Castell from Coed Uchaf

As expected the walk was proving a delight with the hills quiet and sun bathed and the opportunity to meet and talk with local farmers who in the main are an ever reliant, friendly and knowledgeable group of people.

It was only a short walk down to the next connecting bwlch past wooded groups of stunted oak, the leafs of which cast out an early summer beauty.  This section of the walk was an absolute joy, it was as if the hills were transferring me from one land to another and between was a myriad of small oak woods, old and fixed with seasonal change bringing growth and colour, they led me from the bwlch to steepening ground and the next hill of the day; Castell.

Stunted oak

This hill had stood out from afar, and although those of Craig yr Aderyn are more dramatic in nature, this hill gave a dominant profile from the south and was dotted with stunted oak on its lower slopes, with its higher bringing expansive views.

Looking back on my inward route with Coed Uchaf, Foel, Foel Cocyn and Foel Tyddyn y Berllan all in view

Once the summit of Castell was Trimbled I headed down to the next bwlch which was close to a wet area which brought contrast to the land.  Just three hills remained to survey and these were more dramatic in nature with rugged slopes and plummeting cliffs which contrasted with the greened grazing land of the hills already visited.

Gathering data at the summit of Castell

Coed Uchaf

The next hill I visited is unnamed on the map and an individual name for it was not known amongst the farmers who I had met during the walk and then later visited, it has two 231m map heighted summits, their high points each close to prominent cairns, both were Trimbled before the hill’s connecting bwlch was also surveyed.

The summit of the next hill has a large and ancient cairn at its high point, which has now been fashioned to incorporate a wind shelter, local knowledge does not differentiate this hill from its lower and adjacent north-westerly hill, and both are known as being a part of Bird’s Rock / Craig yr Aderyn.

Gathering data at the summit of Craig yr Aderyn (SH 647 065)

Only three surveys now remained and after the bwlch for the lower of the Craig yr Aderyn hills was surveyed I followed the path toward its summit.  Looking back the upper northerly section of the higher hill plummeted downward in a great cliff leading to the flat topped summit of Tap y Botel, this is another locally known name and this small hill is dominated by its near neighbours and yet it is also dramatic in nature sitting as a small bulk of a hill in what can be considered as being part of mountain land.

From this last summit of the day the view mesmerized as the Afon Dysynni slowly ebbed toward the sea in the beautiful greened valley of the Dysynni, and above were the hills; pastoral green and inviting with Cadair Idris dominating the opposing view at the head of the valley.

The view down Dyffryn Dysynni from the summit of Craig yr Aderyn (SH 643 068)

Once data were gathered I left this hill and followed my inward route back up to a fence line before connecting with a path that led down to a gate and the narrow paved road leading toward the old house of Rhiwerfa.

Gathering data at the summit of Craig yr Aderyn (SH 643 068)

When I reached the paved road I sat on the grassed bank beside it and luxuriated myself in the afternoon sun, and ate a chocolate bar and sandwich, my first nourishment of the day.  Above the emerald profile of the higher of the Craig yr Aderyn hills shone down with green piercing hue.

Craig yr Aderyn (SH 647 065)

The road was my access point back toward my car at Dolgoch, but before the path through the wood that would take me downward, one survey remained, this was the critical bwlch of Castell and it is positioned in a field next to a relatively new house which is close to the old house of Rhiwerfa.  As the Trimble gathered its last and seventeenth data set of the day I stood in shade happy in the knowledge that all points I had wanted to survey had been Trimbled and another seven P30s and one sub had been visited.

Fern and bluebells

Gathering data at the critical bwlch of Castell

Once the Trimble was packed away I followed the paved lane down to the next corner and then a steep path through a wood leading toward the house of Tyn-y-coed-uchaf, the path now levelled and continued south-westward toward the B road and after 11 hours on the hill, my awaiting car at Dolgoch.

Survey Result:

Foel (significant name change)

Summit Height:  288.3m (converted to OSGM15)

Summit Grid Reference:  SH 63297 04583

Bwlch Height:  257.7m (converted to OSGM15)

Bwlch Grid Reference:  SH 62971 04432

Drop:  30.6m (200m Sub-Twmpau reclassified to 200m Twmpau)

Dominance:  10.61%

Foel Cocyn (significant name change)

Summit Height:  312.9m (converted to OSGM15, Trimble GeoXH 6000)

Summit Grid Reference:  SH 62455 04290 (Trimble GeoXH 6000)

Bwlch Height:  62.5m (LIDAR)

Bwlch Grid Reference:  SH 67118 06459 (LIDAR)

Drop:  250.4m (Trimble GeoXH 6000 summit and LIDAR bwlch)

Dominance:  80.04% (Trimble GeoXH 6000 summit and LIDAR bwlch)

Foel Tyddyn y Berllan (significant name change)

Summit Height:  232.8m (converted to OSGM15)

Summit Grid Reference:  SH 63481 05158

Bwlch Height:  200.3m (converted to OSGM15)

Bwlch Grid Reference:  SH 63494 04961

Drop:  32.5m (200m Sub-Twmpau reclassified to 200m Twmpau)

Dominance:  13.94%

Gamallt

Summit Height:  288.4m (LIDAR)

Summit Grid Reference:  SH 66549 06761 (LIDAR)

Bwlch Height:  80.1m (converted to OSGM15)

Bwlch Grid Reference:  SH 64227 05008

Drop:  208.2m (LIDAR summit and Trimble bwlch)

Dominance:  72.21%

Coed Uchaf (significant name change)

Summit Height:  216.5m (converted to OSGM15)

Summit Grid Reference:  SH 64901 05582

Bwlch Height:  175.5m (converted to OSGM15)

Bwlch Grid Reference:  SH 65174 05620

Drop:  41.0m

Dominance:  18.95%

Castell (significant name change)

Summit Height:  267.5m (converted to OSGM15)

Summit Grid Reference:  SH 65561 06144

Bwlch Height:  179.1m (converted to OSGM15)

Bwlch Grid Reference:  SH 65917 06266

Drop:  88.4m

Dominance:  33.05% (non Lesser Dominant status confirmed)

Pt. 230.2m

Summit Height:  230.2m (converted to OSGM15)

Summit Grid Reference:  SH 64855 06337

Bwlch Height:  203.2m (converted to OSGM15)

Bwlch Grid Reference:  SH 64807 06441

Drop:  27.0m

Dominance:  11.73%

Craig yr Aderyn (significant name change)

Summit Height:  257.4m (converted to OSGM15)

Summit Grid Reference:  SH 64703 06582

Bwlch Height:  171.0m (converted to OSGM15)

Bwlch Grid Reference:  SH 65190 06417

Drop:  86.4m

Dominance:  33.56% (Lesser Dominant status confirmed)

Craig yr Aderyn

Summit Height:  232.5m (converted to OSGM15)

Summit Grid Reference:  SH 64367 06866

Bwlch Height:  181.0m (converted to OSGM15)

Bwlch Grid Reference:  SH 64569 06814

Drop:  51.5m

Dominance:  22.14%

For further details please consult the Trimble Survey Spreadsheet