Zamami Island, Okinawa, Japan
Zamami Island belongs to the Kerama Island group which are known for the world's most transparent emerald green waters (50-60m transparency). Those islands are also known as one of the world's best diving destinations, having a number of coral species and marine lives as large as those in the Great Barrier Reef. (Over 400 types of corals, 5 types of sea turtles, mantarays, whalesharks, dugons and many kinds of tropical fish species all live around Okinawa.)