The Huai Kha Khaeng Wildlife Sanctuary (Thai: เขตรักษาพันธุ์สัตว์ป่าห้วยขาแข้ง, pronounced [kʰèːt.rák.sǎː.pʰān.sàt.pàː.hûa̯j.kʰǎː.kʰɛ̂ŋ]) is in Uthai Thani and Tak Provinces, Thailand. The park was established in 1974, and is part of the largest intact seasonal tropical forest complex in Mainland Southeast Asia. It, coupled with the Thungyai Naresuan Wildlife Sanctuary was declared a World Heritage Site by the United Nations in 1991. Together, the two sanctuaries occupy 622,200 hectares. As of 2014 it still contained viable populations of large mammals, including gibbons, bears, elephants and Indochinese tigers, although like all other sites in mainland Southeast Asia, some species (e.g., rhinoceroses) have disappeared or have experienced severe declines.
