Tintagel Castle is a medieval fortification located on the peninsula of Tintagel Island adjacent to the village of Tintagel, North Cornwall in the United Kingdom.

In about 1480 the antiquary William Worcestre gave Tintagel as the place of Arthur's birth as well as his conception; and in 1650 the name King Arthur's Castle is first found. By this date references to King Arthur and to the castle had become an inextricable mixture of local folklore and literary legends.