The Dong Phayayen-Khao Yai Forest Complex spans 230 km between Ta Phraya National Park on the Cambodian border in the east, and Khao Yai National Park in the west. The site is home to more than 800 species of fauna, including 112 mammal species (among them two species of gibbon), 392 bird species and 200 reptile and amphibian species. It is internationally important for the conservation of globally threatened and endangered mammal, bird and reptile species, among them 19 that are vulnerable, four that are endangered, and one that is critically endangered. The area contains substantial and important tropical forest ecosystems, which can provide a viable habitat for the long-term survival of these species.