Cozumel

Cozumel, the largest inhabited island in Mexico, is famous for its chain of reefs and 18 miles of protected coastline. The best known is Palancar, with coral walls, caves and tunnels covered in sea fans.

Shallow areas like Chankanaab park are perfect for snorkeling, and the Cozumel channel is one of the best sport-fishing grounds in the area — dolphins often follow boats across.

San Miguel, the island’s town, keeps a relaxed atmosphere with crafts and jewelry shops. Passenger ferries connect it with Playa del Carmen, and cruise ships dock at its piers.