Khaoyai National Park spreads across 4 provinces in eastern Thailand. Nakhon Nayok, Prachin Buri, Nakhon Ratchasima and Saraburi. The park is very significant in the region, having been designated as an ASEAN heritage park. It covers 2,165.55sq.Km of forest land in the Panom Dongrak mountain range, previously know as the Dong Payayen or Dong Payafai mountain range. Khaoyai has a very important function as a headwater for several rivers and creeks, It is also home for a great diversity of flora and fauna and contains spectacular scenery.