From South Wales Bouldering Guide Wiki
It is at an obscure crag called Ynysyboeth, to get there you need to head to the Gap, From here, ramble to the top of the hill and then down the other side. A losing fight with a hill of bracken and burnt trees ensues; don't wear shorts! The crag is at the bottom on the right. N.B. There is no path to the crag so it will be a fight. The route is on the obvious square freestanding boulder at the left of the crag. On this, there is one route of quite exceptional quality on the leaning square arete.
The exact location can be found at http://www.ukclimbing.com/logbook/crag.php?id=8238
- Laughing and Forgetting V4 A short but powerful problem. From low crimps, position your feet very carefully, then dyno to the flake. Finish easily. To do this problem statically using the tiny crimps and pinches on the arete itself would be a phenomenal feat. F.A Jamie Maddison 01/03/2009.
A picture of Jamie on this problem can be found here.