The Samui archipelago holds some of the best dive sites in Southeast Asia. Many of the sites are not only spectacular but also suitable for beginners as they are in shallow waters of protected bays.
While there are good dive sites around the main tourist islands Samui and Phangan, the 'Mecca' for divers is Tao Island at the far north end of the island group. Tao, which means turtle, has plentiful accommodations and dozens of dive companies to fit you out.