Marine For many deep-sea divers and snorkeling enthusiasts around the world,Koh Tao, the picturesque pearl in the Gulf of Siam has been a favorite destination. The island is surrounded by coral reefs and has only been under development since 1993. Diving schools with the latest PADI certified equipment employ professional European and North American instructors and offer courses at the most inexpensive rates in the world. Since many of the divers are below sea level during the daytime you will find the beaches quiet and ideal for couples wanting to get away from it all or family fun in the sun.