What to Do in Khao Sok National Park

Khao Sok protects one of the last intact stretches of rainforest that once blanketed the Sunda shelf during the last ice age, making it roughly 160 million years old. The canopy here reaches 65 meters in places, with emergent dipterocarp trees older than most European cathedrals. What to do in Khao Sok National Park depends on whether you stay near the park headquarters or venture to Cheow Lan Lake, an hour east by road. The main trail network begins at the visitor center in Khlong Sok subdistrict. Short loop trails like the 4-kilometer Ton Kloi Trail follow rivers through lowland forest where you'll hear white-handed gibbons calling at dawn. Longer routes push deeper into the interior, crossing streams on bamboo footbridges and passing giant buttress roots wide enough to shelter a family. The park's signature species, the Rafflesia kerrii, blooms unpredictably between January and March; rangers track active buds and will point you to flowering sites if you ask. Leeches are common year-round, heaviest during the monsoon months of October through December. Cheow Lan Lake occupies the park's eastern third, created in 1982 when the Ratchaprapha Dam flooded the valley. What remains is a maze of submerged peaks and floating accommodations only reachable by longtail boat. Day trips from the lake's main pier include kayaking into hidden lagoons, swimming beneath waterfalls, and hiking to Nam Talu Cave, where you wade chest-deep through passages lit only by headlamp. Overnight stays at raft houses let you wake to the karsts emerging from morning mist, a landscape that inspired the limestone islands in Avatar's Pandora. Wildlife sightings here include Asian elephants drinking at the shoreline, hornbills crossing the water at dusk, and occasional clouded leopard tracks on remote trails. Guided treks are the safest way to navigate deeper routes. Independent hiking is permitted on marked trails near headquarters, but anything beyond the 8-kilometer mark requires a licensed guide. The park's ranger station posts daily wildlife sightings and trail conditions on a chalkboard near the entrance. Cell reception ends two kilometers into the forest.