40 miles west to Aberdaron then 25 minutes on the boat to Bardsey Island. A pilgrimage you'll never forget, whatever your religion. Only 2,000 day visitors a year are allowed onto this pristine nature reserve. Seals, puffins, razorbills, kittiwakes, choughs, manx shearwater, risso's dolphins and the spirits of thousands of saints. Was this really Arthur's final retreat?