Cheow Lan Lake

Cheow Lan Lake, also called the Ratchaprapha Reservoir, is a large freshwater reservoir in Surat Thani province, southern Thailand, created by the construction of the Ratchaprapha Dam. The flooded valley contains dramatic limestone karst towers and forested islets within Khao Sok National Park.

The lake is visited for boat trips, guided canoeing and overnight stays in floating bungalows positioned among limestone islands. The karst peaks rise directly from the water, creating a distinctive landscape of steep cliffs and sheltered coves.

The reservoir formed after the dam was completed in the late 20th century; the inundation created the extensive lake and its isolated limestone islands, which are now framed by protected forest. Visitor facilities and boat operators are concentrated at a few embarkation points outside the park.

The lake lies within the Khlong Saeng valley of Surat Thani province and is administered as part of Khao Sok National Park, in southern Thailand; access is by road from nearby towns and by boat from the lake piers.

• Creation: Formed by the construction of the Ratchaprapha (Cheow Lan) Dam in the late 20th century, creating a large freshwater reservoir with steep limestone islands and forested shores.
• Accommodation and access: Floating raft-house accommodation is a common overnight option on the lake; trips are run by licensed operators from nearby piers.

What to See #

• Ratchaprapha Dam (reservoir dam): A concrete gravity dam on the Khlong Saeng river that created the reservoir; it functions as the lake's main control structure and is the typical embarkation point for boat trips into the reservoir.