I parked by the little chapel at the foot of the hill and from there we scrambled through the bushes and into the hillfort. It's a big one,not high up or impressive earthworks but it does cover a large area. Fantastic views south of the Menai straight and mountains east over Puffin island to Llandudno west across the beach and island and north is across the sea. I think I even found Arthurs table with seats but I couldn't find the entrance.
This hill fort overlooking the sea contains 'Bwrdd Arthur' - Arthur's Table. If you search you can find a large circular stone with 24 'seats' around. The geologically-minded might interpret this as part of a limestone pavement.