Corfu

The island is one destination with two embarkation points about 16 km apart. Achilleon Diving Center has run out of Paleokastritsa on the west coast since 2001, with Corfu Dive Club based at the Elly Beach Hotel inside the same gulf since 2010; most of their sites are a short hop, with Skeloudi five minutes from shore and only Kolovri needing a longer run of under 30 minutes. Apollo Dive Center works the north-east coast from Nissaki, ten minutes by boat from Corfu port, with a 15-minute ride to Agni. Beginners can start straight off the sand at Agia Triada Beach, which shelves gradually from the shore.

The west-coast rock is what sets Corfu apart: dive-site listings call it the cavern diving capital of the world, and the Hole of Ha is an easy cavern that runs inside a mountain with no roof, so the trees around the opening are visible from below. The Chimney is a literal vertical shaft from 28 m to 5 m, kept for cave-certified divers. Donald's Place adds a drop-off and a cracked, crevassed wall where morays peer from the holes. Off Nissaki the ground is reef and steel: Agni reef runs from 1.5 to 30 m with a wreck at 40 m, a WWI steamer's anchor and chain lie at 26 m, the Anonymous Wreck sits at 32 m, and the City of Peraus ferry rests at about 43 m.

It suits divers who want caverns and swim-throughs without cave training, since the Hole of Ha is rated easy, plus beginners on the shore entries and shallow reefs. Advanced divers get Kolovri, an offshore complex averaging 30 m that demands CMAS two-star or AOW, where the current can turn strong for a day or two after a mistral blow; depth and boat traffic are the flagged hazards elsewhere. Dedicated wreck divers have steel here but nothing intact and famous, and are better served by the Zenobia at Larnaca; those after big animals should look past the Ionian entirely.