A companion to the larger hillfort crowning Mynydd y Dref (Conwy Mountain) to the east, this site is well worth visiting for the sea views alone. To be honest traces of ramparts are a bonus.
Park at the summit of the impressive Bwlch Sychnant between PenMaenMawr and Conwy - ensuring your handbrake works beforehand, of course - and follow the North Wales Path northwards for a while (with fantastic views down the valley) before veering left to ascend to the fort. Remains of a small(ish) roughly circular enclosure crown the rocky summit overlooking the sea.
Retracing your steps, the path continues north-east to Mynydd y Dref and, if you've got the legs, Conwy. Superb.......