Introducing Khao Yai National Park
Up there on the podium with some of the world's greatest parks, Khao Yai is Thailand's oldest and most visited reserve. Covering 2168 sq km, Khao Yai incorporates one of the largest intact monsoon forests remaining in mainland Asia, which is why it was named a Unesco World Heritage site (as part of the Dong Phayayen–Khao Yai Forest Complex). Visiting independently is quite easy, as the mostly English-speaking staff at the visitor centre are very helpful.
Rising to 1351m at the summit of Khao Rom, the park's terrain covers five vegetation zones: evergreen rainforest (100m to 400m), semi-evergreen rainforest (400m to 900m), mixed deciduous forest (northern slopes at 400m to 600m), hill evergreen forest (over 1000m) and savannah and secondary-growth forest in areas where agriculture and logging occurred before it was protected.
Around 200 elephants tramp the park's boundaries. Other mammals include tigers, leopards, bears, gaur, barking deer, otters, various gibbons and macaques and some rather large pythons. Khao Yai's bird list boasts 392 species, and one of Thailand's largest populations of hornbills lives here, including the great hornbill (nók gòk or nók gah·hang).
The main entrance is south of Pak Chong, but there's a second, seldom-used southern entrance in Prachinburi Province.
Read more: http://www.lonelyplanet.com/thailand/nakhon-ratchasima-province/khao-yai-national-park#ixzz3zOWw2oFC