by remus
From the parking, follow the road towards Blue John Cavern. Go through the gate to your left and follow the path to another gate. Go through here, but instead of following the large path follow a broken wall rightwards up the hill for ~75m before following a vague track that contours round the hill. Your are aiming for a tree sticking out of the crag, almost straight up the hill from Treak Cliff Cavern. Alternatively you can bash straight up the hill from Treak Cliff Cavern but it is a bit of a slog, and likely to attract attention.
If you see shiny rocks on the ground then leave them alone.