The Caribbean's tiny Cayman Islands maintain a huge reputation in the diving world, with lush reefs, plunging walls, and an extensive marine park system. Grand Cayman, Cayman Brac and Little Cayman are perched atop the awesome Cayman Trench, a vast submarine mountain ridge above the deepest water in the Caribbean. For divers, this means only minutes between leaving the sandy beach and reaching the breathtaking abyss and its more than 250 moored sites. This useful guide describes how to best explore the gorgeous islands - both underwater and on land - and includes a thorough list of dive operations.