The history of Khao Sok national park starts 300 million years ago. Rising oceans created a shallow sea with conditions perfect for the growth of coral. The result was a massive reef which stretched from China to Borneo. Eventually, more sediment buried this reef deep below the surface, and the pressure compressed the coral into limestone. It is this limestone that forms the Karst mountains we see today!

About 60 million years ago, the Indian tectonic plate collided with the Eurasian plate and as a result formed the Himalayas. At the same time, Thailand was rotated clockwise and moved to the south-east as the Himalayas rose. The ancient, buried limestone was thrust up, folded, faulted, and then eroded into its current form.

Between 300A.D. and 1300 A.D., Khao Sok was home to an ancient trade route between China and India. Ancient Hindu statues have been found in nearby Kapong and Pra Narai.

The Modern history of Khao Sok national park

Until the modern era, Khao Sok has been sparsely settled. In the last century, however, small villages and fruit plantations were established.

In the 1970’s Khao Sok served as a stronghold for student activists fleeing Bangkok, following the military crackdown on October 6, 1976. Their headquarters and hospital were located in the area of Namtaloo cave on Khao Sok Lake. For eight years they kept the Thai military at bay.

The students also held off logging companies that would have cleared massive areas of the forest that became Khao Sok National Park. Everyone avoided hunting, as unnecessary gunshots on either side would give away positions. Additionally poachers kept out of the occupied areas. As a result, wildlife thrived in an active combat zone, and to this day the area around Cheow Lan remains one of the best places in Thailand to see wildlife.

On 22nd December, 1980 Khao Sok nationalpark was established. At the same time the Electricity Generating Authority of Thailand (EGAT) surveyed the area as a possible site for a dam and generating plant.

in 1982 the Rajaprabha Dam was built.This created the 165 square kilometer Cheow Larn lake inside the park.