Valencia slate quarry is on the north side of the island, overlooking the Atlantic Ocean, about 3 km from Knighstown Village.   The large cavern contains a working slate quarry and cutting works, so access is restricted to the front of the site.  The cavern is approximately 80 meters wide and 20 meters high there is small grotto right at the top with a statue of the virgin Mary, which was placed there is 1954 at a time when the quarry was not in operation.  There is also an altar and fountain at the entrance to the cave.

When you look out to sea you get a birds eye view of the light house below, with good views towards Cahirciveen and the mountains to the east, and also accross the bay to Dingle and the Blasket Islands.   There are hills all around the cavern which are good to climb but you will need good boots and be sure footed.  There are the remains of a chimney which is part of the old quarry works from the 19th century.   There is also a working quarry below so you will have to look out for heavy machinery, and there is plenty of places to park.

The walk up from Knightstown is a very pleasant walk though wooded lanes with spectacular views out to the Atlantic and back across the island.  It is all uphill so may be a little taxing for those with poor fitness levels.

The are no eating facilities at the top, however the "Lighthouse cafe" is located about a kilometre away down the hill, and is open in the summer months serving sandwiches, salads, coffees and the like.