Mapping Mountains – Trimble Surveys – Cefn yr Ystrad

02.09.23  Clo Cadno (SO 118 162) 

Clo Cadno (SO 118 162)

Clo Cadno is an attractive looking hill with a line of small crags encircling its upper western fringe.  Looking from its opposing ridge to the north-west it forms one of three hills, with the other two further to its north-east.  These can easily be combined and included with an ascent of their higher neighbour; Mynydd Llangynidr (SO 123 151).  The land hereabouts is open and consists of moorland, therefore not a place to linger when cloud is upon the hills.

My priority for the day was Clo Cadno, this hill is one of five remaining for a completion of the Welsh Highlands – Uchafion Cymru list.  These are the Welsh hills at and over 500m in height that have 15m minimum drop.  The current total is 630, it was more but LIDAR has deleted a number over recent times.

I was out with Aled, who I met in Caersŵs before driving further south to the heads of the valley’s road and onward heading north on a minor road through what is reputedly Wales’ highest village; Trefil.  Approaching the hill from this direction gives an easy ascent from what is now regarded a private quarry road, but was once classified as a B road.  This road is now rough in its upper section and eventually leads to the quarry positioned just below the summit of Cefn yr Ystrad (SO 086 137).  The last time I used this quarry road was in August 2015 when along with Mark Trengove we got locked in, not realising that the barrier across the road just above the last house in Trefil was locked later in the afternoon.  This was on a weekday and necessitated getting a key from the quarry to let us out.  Today was a Saturday and I was unsure whether the barrier would be unlocked during the day.  Driving up the road past the houses of Trefil we approached and there the barrier was; firmly locked across the road.  It had taken two hours to drive here and it seemed our plans would have to be quickly amended.

We stood beside the barrier and debated the best course of action, during this a tractor slowly rumbled up the road and pulled up beside the barrier, the driver obviously had a key and was heading toward fields at the far side of the quarry to work, and after a quick discussion the farmer suggested we follow him up the road and as long as I was back at the barrier within 2½ – 3 hours he would then let me out as he headed back home.  All was saved, although we did have to alter our plans as Aled had suggested surveying Garn Caws (SO 129 167), which as its name implies is crowned by the remains of an ancient cairn and dependent upon what rock is taken as its high point this may alter its current Welsh Highland Sub status. 

Aled's assessment of what was deemed the highest natural rock (marked with a yellow cross) compared to a LIDAR image for Garn Caws (Photo: Aled Williams)

However, a maximum of three hours to visit Clo Cadno, survey its summit, visit the sub positioned at SO 122 167 and continue to Garn Caws and survey its summit before Aled headed over to Mynydd Llangynidr and the Chartist Cave, whilst I headed back to survey the connecting bwlch of Clo Cadno, would in all probability not be sufficient.  Therefore, as my priority was Clo Cadno I was more than happy to just visit and survey its summit.  This would give me an unrushed day and allow a slow plod there and back and a sit in the sun waiting for the farmer to come back down from his fields.

Our plans went beyond this though as after these hills Aled wanted to head toward Cefn yr Ystrad and visit a further four subs, including two impressive rocky lumps left in situ in the quarry and then head down the track leading toward Tor y Foel (SO 114 194), where I would pick him up.

With our plans amended, but the day’s walking and surveying saved, we set off walking at 10.00am on a rough track which was once a part of the classified B road.  This soon headed steeply downhill, whilst our continued route followed a good green track which headed toward Clo Cadno. 

A convenient place to park

It was grey with an oppressive stillness in the air as we ascended.  The forecast gave for warming conditions after the morning murk was burnt off.  The cloud was only just above the tops we headed for, with more under murk to our east. 

Heading off on the path toward the summit of Clo Cadno

From this direction it was only a short walk to the summit of Clo Cadno, but still very enjoyable as we continued up the green track passing one or two wet, boggy patches of land.  Just before the crags we left the main path and were soon standing on the westerly upper part of the hill, just a few minutes’ walk to our east was its nondescript high point.  This consists of low heather and moor grass.  Once we had checked the LIDAR co-ordinates for the summit position which Aled had produced during the updating of the Welsh Highland list with new Welsh LIDAR, I soon had the Trimble positioned on top of my rucksack and as I activated it to gather data, Aled headed off to visit the two subs and inspect the summit cairn of Garn Caws. 

Gathering data from the summit area of Clo Cadno

As the Trimble gathered its allotted five minutes of data I stood away from it so as not to interfere with satellite reception and looked behind me and farther to the east as the grey mornings murk slowly descended.  The high ridge of Mynydd Llangynidr was now under the murk and the cairn atop Garn Caws was only just free of the veil of cloud.  I hoped Aled could do what he wanted and not have the prospect of a couple of hours wandering the wild moors of south Wales under a bed of grey cloud. 

The onward route for Aled, with the summit of Garn Caws on the right

Once allotted data were gathered and stored, I closed the equipment down, took a few photos and then packed it away and started back toward its western top.  Once there I avoided the crags and re-joined our inward route, only stopping to take a few photos of mountain ponies, with one or two making cursory approaches before their timidness backed them away. 

A misty scene in the background with the first glimmers of direct sunlight 

As I approached the rough track leading back to my car a tractor swung on to it from the quarry road.  As it got nearer I flagged it down.  Its driver; Kevin Morris was more than happy to talk about the hills, and as I pointed to one he would give me the name he knew it by.  To my knowledge two of the names he gave have never appeared on an Ordnance Survey map. 

Mountain Ponies on Clo Cadno

After thanking Kevin for his time I waved him off and continued up the slight rise back toward my car, as I did so I noticed a figure emerging from the green path on to the rough track, it was Aled.  We arrived at the car at about the same time, as the murk had descended he decided to just visit the two subs beyond Clo Cadno and also inspect the cairn on Garn Caws, Mynydd Llangynidr and the Chartist Cave could wait for another day. 

Kevin Morris

I then drove further up the quarry road until it got particularly rough with large watery pot holes looking as if they could swallow my car.  After dropping Aled off I drove back down the quarry road, stopped the car to change and then continued down to wait at the barrier, sitting in the emerging sunshine whilst chatting with the occasional walker.  Soon a man with the farmer’s key turned up, he had passed me as I had driven down the quarry road.  I thanked him as he unlocked the barrier and let me out. 

The higher of the two quarry subs (Photo: Aled Williams)

All that remained was to follow my hand written instructions on how to connect with the Llangynidr road from Trefil, after this it was up the steep road leading south of Tor y Foel and further down a track until this merged in to an earthen path.  Here I stopped, sat on a convenient stone bench whilst enjoying the afternoon sun, reading a book and chatting with all manner of people with runners, dog walkers, cyclists and walkers all heading this way and that.  An hour or so after arriving, a weary looking Aled wandered down the path with stories of impressive rocky quarried subs, with one summit that he only touched and not stood on due to large fissures in the rock. 

The lower of the two quarry subs (Photo: Aled Williams)

On our way back we stopped for a meal, sitting outside the Wheelwright Arms in Erwyd enjoying good pub grub in the afternoon warmth, it proved a good way to end an excellent day.  

 

Survey Result:

 

Clo Cadno                                  

Summit Height:  530.3m (LIDAR) (significant height revision)

Summit Grid Reference:  SO 11849 16247 (LIDAR)

Bwlch Height:  513.6m (LIDAR)

Bwlch Grid Reference:  SO 12197 15992 (LIDAR)

Drop:  16.7m (LIDAR) (Welsh Highland P15 addition)

Dominance:  3.15% (LIDAR)

                                       

 

For further details please consult the Trimble Survey Spreadsheet