Most popular though is a trip to the Blue Cave in the south-east part of the island. It has an aperture like an eye bisected by the waterline.
You have to lie down in the boat to pass through, then you have the otherworldly experience of a dense and thrilling blueness in a cathedral-like sea cave with stalactites and twisting columns of rock.
The huge boulders 23 metres down on the seabed seem close enough to touch. To swim there is how you’d imagine it would feel like to float in space.