Khao Sok National Park, is a park that is located in the province of Surat Thani. Its area is 739 km² and includes the 165 square kilometer Cheow Lan Lake, contained in the Ratchaprapha Dam. Furthermore, it is traversed by a limestone mountain range from north to south with a high point of 950m. The park is the largest area of primeval forest in southern Thailand and is a remnant of rainforest that is older and more diverse than the Amazon rainforest.