Cheow Lan Lake

Cheow Lan Lake is a large artificial reservoir within Khao Sok National Park in Ban Ta Khun District, Surat Thani Province, southern Thailand. Created in 1987 by the Ratchaprapha Dam on the Khlong Saeng River, it covers about 185 square kilometers. Surrounded by limestone karst cliffs and rainforest, the lake is known for its emerald water, submerged limestone peaks, floating raft houses, and wildlife, and is a major ecotourism destination.

Visitors can expect a vast emerald reservoir dotted with towering limestone karst formations rising from the water, surrounded by dense evergreen rainforest of Khao Sok National Park. Access is by longtail boat from Ratchaprapha Dam pier. Visitors explore by boat tours, kayak, visit caves such as Nam Talu and Coral Cave, view wildlife, and stay overnight in floating raft houses with simple rooms and restaurants. The setting is remote and tranquil with no road access across the lake.

Created in 1987 with the completion of the Ratchaprapha Dam (Rajjaprabha Dam) on the Khlong Saeng River, a tributary of the Phum Duang River, as a hydroelectric and irrigation project. The reservoir flooded approximately 185 square kilometers of former forest and villages, forming the lake within Khao Sok National Park.