2. Palau, Micronesia
With wall dives, blue holes and underwater caverns, Palau in Micronesia is another world-renowned dive site. The Blue Corner Wall is one of the most popular spots, where reef sharks are known to gather to feed in current. Many divers hook themselves to the wall while they take in the sheer beauty of the range of curious barracuda, sharks, cuttlefish, wrasses, turtles, orcas, shellfish, tuna and anemones.