Castle Quarry Slab is an attractive face of quarried limestone, once home to a few scary early '80s trad routes and now hosting a clutch of smeary sport routes. This provides a welcome change from the normal limestone steepness, giving delicate friction routes of a significant length.
The crag is fairly sheltered and the slab faces south so it can be a fine place to climb on a cool winter's day, conversely the rock will feel rather slippery under summer sun.
From the National Trust car park below Craig Fawr, cross the road and start to head eastwards on the narrow road. After just a few metres, turn right downhill on another narrow road, signed '5T Just for Access'. After about 100m, cross a stile on the right onto a public footpath; follow this downhill for about 150m crossing three stiles, then take the right fork into the old quarry. The climbs are found on the left.