The relatively modest cairn upon Pen Rhiw-ddu makes a fine hors d'oeuvre for a visit to this, one of South Wales' finest - and largest - upland cairns at almost 3.5m. Duw, it's big! What's more, it crowns a very unfashionable 523m summit, far out on the western fringes of Y Mynydd Du. Although the 'Beacons Way' passes close by - not that you would guess, it has to be said - I can not imagine any long distance walker lingering here for very long, if at all. Such people tend not to be interested in 'piles of old stones'.
The cairn dominates the (approx) western horizon from Carn Pen Rhiw-ddu and, if it wasn't for the wind, I'd have sworn I could hear it whisper 'visit me, you know you must....'. Or perhaps that was just the 'E' numbers from too much Easter chocolate kicking in - why, we even had to stop on the way from Bridgend to get some more. Whatever the cause, the effect is the same. We have no choice but to comply. At a little over half a mile, the distance between the two monuments is by no means great in hillwalking terms. But bear in mind that this is a 'proper' mountain landscape. Peat hags abound, the long grass is liberally sprinkled with 'ankle breaker' rocks to catch the unwary... and I shudder to think what it would be like in mist. Quarter may be asked, but will definately not be given up here.... especially with the wind gusting at 40-50 mph. Nice. No, really, I find few things more intoxicating than being out in inclement weather when you're adequately protected. Not that a family unit of wild ponies, sheltering in a hollow, would appear to agree. They probably have more sense than crazy English people. Curiously one mare, heavily pregnant, judging by the size of her belly, stands aloof from the group, munching grass furiously. Hell, encountering these fantastic creatures is one of the joys of these hills, it really is.
Carn Pen-y-Clogau steadily grows larger as we approach until... wow! Some people certainly spent an awful lot of time building this. An awful long time, indeed. Struggling to the top in the wind, I'm saddened to discover that, even here, the 'shelter building muppets' have been at work. But such is life, I guess. Na fe bois, Felna Mae. Excitedly I point out Castell Carreg Cennen, standing a'top its unfeasibly dramatic crag away to the almost exact west. Then, to the south-west, a line of suspicious 'humps' crowning a ridge in seriously evocative fashion. I check the map - Tair Carn Uchaf and Tair Carn Isaf. How much more has this country to offer? The vibe here is fantastic and I wish we had more than a couple of hours. But what a couple of hours...
Carn Pen-y-Clogau is not the only monument to grace this wild mountain top. According to Coflein:-
CARN FATHO [Bronze Age Round Barrow] - SN71581855 - Some 130m W of Carn Pen-y-clogau lie the remains of another cairn. It is badly denuded and consist of a consolidated ring measuring overall about 10m (E-W) by 8.5m and 0.4m high, infilled with loose boulders. Further boulder scatter to the N may have come from the cairn. This is perhaps the site of Carn Fatho, a cairn believed to be located near to Carn Pen-y-clogau. It was possibly used as a parish boundary marker.