Substantial remains of the simple abbey church, founded in 1198 by Maredudd ap Cynan for the Cistercian order.
This enormous 19th-century neo-Norman castle sits between Snowdonia and the Menai Strait. It's crammed with fascinating items, such as a one-ton slate bed made for Queen Victoria, elaborate carvings, plasterwork and mock-Norman furniture.
There are extraordinary views of the Llŷn Peninsula from this unusual little village. Trefor developed thanks to the local granite quarry. Its small harbour became extremely busy in the days when the granite was shipped to all over Europe.
Trefor, Gwynedd, LL54 5LB