Khao Yai National Park is one of Thailand's oldest and most visited natural reserves, stretching over 2,168 square kilometers across four provinces in the heart of Thailand's eastern Isaan region. Founded in 1962, it's the country's third-largest national park and was declared a UNESCO World Heritage Site as part of the Dong Phaya Yen–Khao Yai Forest Complex. Characterized by its diverse terrain, the park's landscapes transition from lush tropical forests to grasslands and includes numerous waterfalls, the most famous being Haew Suwat and Haew Narok. Khao Yai is a haven for a wide array of wildlife, including elephants, bears, gibbons, and a vast number of bird species. The park features well-marked trails, wildlife observation towers, and visitor centers. The elevation ranges from 400 to 1,000 meters above sea level, leading to a cooler climate, thus making it a popular escape from the heat for locals and tourists alike.
