No special access issues
Park either at the large layby by the reservoir on the road above Rhyd Ddu towards Nantlle, or sensibly by the side of the road where it widens enough for three cars. Walk along the road over the crest of the hill to a farm gate on your right. Cross the gate (carefully) and take a direct line across the field to a break in the wall. From here, follow a vague path, over some steep rocky steps and down the hill to an obvious path running through a narrow rock gully. These are the warm up blocs.
From here, pass through the narrowing and over the little rise, before trending leftwards around the hill and to the right of some old stone buildings. This will see you arrive at the Covid boulder.
After passing the Covid boulder, cross over one of the fallen sections in the wall and up the grassy slope to the main boulder field. The Roohan Roof is back up to your right, the Dog Bloc is in the field directly above you, and both the Pen and the Powed bloc behind the Dog Bloc.
For access to the Cracked Bloc, the Boom Prow, the Sentry Bloc and the Tooth Boulder, cross the wall above you via a rock step/style. The scree slope allows access to most boulders here.
While the crag is on open access land, there is a suggestion that the local farmer is not particularly fond of climbers and even an old anecdote on ukclimbing forums that he has been known to confront climbers. This is old information but does suggest that it would be wise to maintain a relatively low profile.