OUCC Proceedings 13 (1991)

Those people who take the trouble to wander over the eastern part of Wales' Black Mountain area are probably familiar with the sight of a 4m wide river disappearing into the side of an impressive limestone cliff. The name of the river is the Giedd and the sink is, with impeccable Celtic logic, named Sinc y Giedd (NGR SN 810178). The water is next seen some three kilometres away, as the crow flies, in the Mazeways series of Dan yr Ogof cave. It must travel a further 1.5km through known passage before it once again reaches daylight at the mouth of the cave (NGR SN 834160).

Between sink and resurgence, the water falls a distance of 218m and must travel an absolute minimum of 4.5km underground - although experience tells us that the actual distance is sure to be greater than this. The river can take an appreciable amount of water in wet conditions, having a catchment area of 10 square km of very wet Welsh moorland, yet all of the water finds its way underground. Clearly, there is a lot of passage still to be found between Sinc y Giedd and Mazeways - in the so-called "Giedd Series". Dye tests have proved a positive link and indicate a flow time of around 36 hours in moderate water conditions. For those who have caved in Dan yr Ogof, the prospect of further passage of similar quality must make this system one of the most exciting areas of potential in Britain today. Yet, despite numerous attempts, the cave has been very successful at guarding its secrets.

A history of the numerous attempts to find the way on is outside the scope of this article. The obvious leads have all been looked at but have generally posed huge problems to the would-be explorers. Exploration from inside the cave has involved diving, with all its logistical hassles, or digging in unpleasant boulder chokes with no obvious way on. Surface digs have been dominated by two major feats of civil engineering: Sinc y Giedd and Waun Fignen Felen. Of these, only Sinc y Giedd is likely to enter the main river series, with the latter probably joining the Great North Road. Unfortunately, despite a massive involvement in time and effort on the part of the South Wales Cave Club, conditions underground and repeated flooding have prevented even the thinnest of people from getting into the new system. Both digs now lie abandoned.

My real involvement with the area began back in 1985 when I received a telephone call from Gareth Jones, a SWCC member (and old CUCC lag, to boot). "Got this great new dig...near Sinc y Giedd...draughting strongly...in just the right beds...bedrock...stream sink nearby..." It was a familiar tune, and recycled with as much originality as Kylie Minogue's next hit. So, we waited for the worst possible weather and I tagged along for a noncommital look.

After an hour's walking, we arrived at an impressively large, flat-bottomed shakehole (NGR SN 808184), with a peaty stream sinking in one corner. The hole had been chosen not only because it was taking an active stream and was close to Sinc y Giedd, but also because it lay just below an outcrop of a bed of rocks which by then had acquired mythical properties in Gareth's eyes: the Honeycomb Sandstone, a sandy, decalcified limestone bed, exhibiting a distinctive Swiss cheese appearance. Gareth enthusiastically pointed out that it marked the start of the main cave-bearing beds of the area; both for Ogof Ffynnon Ddu and Dan yr Ogof. The Sinc y Giedd people had been digging in the more shattered and less massive upper beds, which had been one of the reasons for their previous failures. At least here we'd be giving ourselves a sporting chance. I figured that, since I probably had very little better to do for the next three years, I'd give it a go.

Whenever the weather was at its worst, we would go to the dig. By now, I had been informed it had a name: the Rusty Horseshoe Dig. Something to do with a bent piece of metal found nearby, I think. Often we would turn up at Penwyllt to see if anybody was interested in helping. Until then, I hadn't realised that Cwm Dwr was such an exciting place. Sometimes we would meet a visiting club who were unfamiliar with the established order of things. "Fancy a walk? Got this great new dig...near Sinc y Giedd...draughting strongly...etc." On one rare occasion, we persuaded Kev Senior to carry a whole door across the moorland, an event that Kev probably still remembers vividly if the amount of whingeing at the time is anything to go by. On the whole, however, most people had far too much sense to stand around in the middle of nowhere getting absolutely frozen.

Within a month or so, we had excavated a short horizontal piece of passage, which led into a 4m shaft. By now, the draught was becoming a wind. The only complication was that it was going "in the wrong direction'. Although situated high up on the moorland, it was draughting out in summer and in during the winter; so you always had the least pleasant underground temperature. As we reached the bottom of the shaft, the roof started to spit the odd stone down on us but, in our zeal to push on, this was ignored and additional shoring was left for another day. When the inevitable happened, I found myself standing in the shaft, while Gareth's ample frame filled the entrance crawl - and my exit - as he attempted to roll a particularly large boulder uphill. With no escape, I pressed myself hard against the rock face as the roof crashed down around me, boulders bouncing off my helmet and back. When it eventually calmed down, the whole shaft was once again filled with debris and I was buried up to my armpits in it. Where once there was a low roof, now lay a large aven full of intimidating boulders just asking to be dislodged. Although I was able to wriggle out, it was to be another six weeks before we managed to dig out my wellies.

The dig was to continue on quite a regular basis for another three years, during which time the spoil heap grew to massive proportions, half a forest and an oil drum were carried up the hillside and the "sharp end" became more and more dangerous and difficult to dig. With nowhere to stash the spoil within the cave, it became necessary to haul it all the way out to the surface. This required a team of at least six people to negotiate a heavy bucket through all the constrictions and bends - and such numbers were becoming impossible to muster. The amount of hanging death became a concern to even the most kamikase amongst us. Eventually, and with much misgiving, it became prudent to "give it a rest and let it stabilise" - a euphemism for grudgingly admitting defeat after so much effort had been put into it by so many people. It had - and probably still has - one of the best draughts I have come across, so it must be connected to something quite significant. And it's in the right beds, etc. Yet, in spite of it having been one of the longest-running and most concerted efforts in the area since the old SWCC digs of previous decades, it too lies abandoned with the rest of them. I have recently been told that the entrance has collapsed, putting the final seal on the project.

If it takes six people three years to dig a hole, how many does it take to find a cave? As recent discoveries elsewhere on the Black Mountain have shown, it can take a chance discovery and minimal effort to get into new cave. Although the eastern area has yet to give up the fight, I believe that it is getting too easy a time. Although it is only an hour's walk from the road, it might as well be on the moon for a great many people. Perhaps the lure of Ogof Ffynon Ddu right on people's doorstep is too strong to entice them away, but until significant numbers take greater advantage of the area's vast potential, little progress is likely to be made. I can't help believing that if the area were in Yorkshire, we'd already have found what is sure to be Britain's best sporting through-trip.

Martin Hicks