Located in the west of Thai Gulf, in the territory of Kuiburi District, Sam Roi Yot Sub District, Prachuap Khiri Khan Province. Khao Sam Roi Yot National Park is Thailand’s first coastal National Park in 1996,covering the area of approximately 98.8 square kilometers. The landscape is high steep limestone mountains by the beautiful coast, matching with plain area stand by the sea, which are marshy beach and shallow sea pond. There are limestones island nearby the coast e.g., Ko Sattakut, Ko Kho Ram, Ko Nom Sao, Ko Rawing, Ko Rawang and Ko Khi Nok. The flat area with Stagnant water through the year on the west of the park is Thung Sam Roi Yot, which is the large freshwater marsh, covering around 36.8 square kilometers.