Phujong - Nayoi National Park located in Boon Trick District, Najahlauy District and Num Yuen District, Ubon Rachathani Province. The area is close to Lao People’s Democratic Republic and Kingdom of Cambodia. It is a part of Phanom Dongruk Mountain Range which consists of many big and small mountains such as Phujong Nayoy, Phujong Numsub, Phujong, Phuchun Dang, Phu Plansung and Phu Planyao. There is productive forest inhabited by a great number of animals. The area has naturally beautiful sceneries, and is about 686 squars kilometers or 428,750 Rai.
Most of the area is mountain range, the source of main rivers of Ubon Ratchathani Province, which consists of montane forest, semi-evergreen forest, mixed forest and deciduous forest so that makes it be productive area and crowded with trees. Soil on the plain of the hill is laterite mixed with limestone. And there also are many different shapes of rocky plains and cliffs such as Pha Paung.
Weather in this area has three seasons.
Plants in this area are of the montane forest, semi-evergreen forest, mixed forest and deciduous forest growing in which clusters approximately 75% of its area. There are densely brackens such as wild champak and many kinds of flowers covering the area for timberland such as iron wood, Burmese ebony, Yang, Krakak (a kind of Dipterocarpaceae), Poo chao, Black wood, Makha and Kae lae (a kind of Moraceae) growing in each forest of its kind.