Type : Island, archipelago
Address : Mueang Chumphon, Chumphon Province
Koh Mattra or Koh Tang Gui is around 7 kilometers in the east of Hat Sai Ri. The white beach is suitable for snorkeling. It is also the location of the National Park Security Guard Unit. Tourists can either set a tent on the beach or stay in the houses of the National Park. At the edge of the island, tourists can observe the fringing reefs to see marine life, such as, Acropora spp. and sea anemone. Aside from the coral reefs, giant clams and hairy leg mountain crabs which like to climb up trees and sound like baby chicks, can be found as well.