The Similan Islands are a stunning archipelago in the Andaman Sea, part of the Mu Ko Similan National Park in southern Thailand. Renowned globally as a top destination for diving and snorkeling, the islands are famous for their crystal-clear turquoise waters, vibrant coral reefs, abundant marine life (including sea turtles), and distinctive massive granite boulder formations. The name "Similan" comes from the Malay word "sembilan," meaning "nine," referring to the original nine islands in the park. The park was later expanded and now consists of 11 islands.