Ratchaprabha Dam is among the most popular places in Surat Thani and a must visit attractions on a visit to Khao Sok. Locally, it is known as Chieo Lan Dam and it was built in 1982 to ensure the water supply to the southern parts of the country. Also, it generates 554 million kilowatt of electricity every hour. The dam is 94 meters high and 761 meters long, and it’s water reservoir (Cheow Lan Lake) covers an area of 185 sq. kilometers. Cheow Lan Lake has given birth to hundreds of small islands and it offers views of stunning limestone mountains. Every year, Ratchaprabha Dam receives thousands of local and foreign tourists.