Mentioned by Lonely Planet Top Choices
Top things to do in Cornwall
"Looming up in the middle of Mount's Bay and connected to the mainland at Marazion via a cobbled causeway, this abbey-crowned island is an unforgettable sight, and one of Cornwall's most iconic images. Initially a Benedictine monastery, and later the seat of the St Aubyn family, it's a must-visit. You can catch the ferry (adult/child £2/1) from Marazion at high tide, but it's worth arriving at low tide so you can walk across the causeway, as pilgrims did centuries ago."