Numtok Samlan National Park (Phraphut Thachai) has its area in Kaeng Khoi Distric, Nong Khae District, Wihan Daeng District and Mueang District, Saraburi Province. During the World War II, Japanese Army occupied and set this area as a shelter, as its result, the forest was destroyed. In B.E. 2503 (1960), the government began to reforest and declared as the conservation forest. It calls Khao Samlan Forest which, locates very near to Bangkok, is a productive forest, and has very beautiful places to visit, such as, mountain and waterfall. Especially, Samlan Waterfall which is well known by traveler. It has a convenient way to visit, and visitor can take one-day trip from Bangkok. Numtok Samlan National Park is about 44.57 squares kilometers, and has been declared a national since June 2, 1981.
The area consists of many big and small mountains and plains in the valley. The highest peak is Khrok Mountain, about 329 meters above sea level. Traveler on the peak can see Saraburi Province’s city and nearby districts very clearly. The forest of this area is the source of many waterfalls and streams, which go to maintain plantation of local people. The surface of this area is clay and sandy soil cover hard soil and rock.
The forest in this area is mixed forest and deciduous forest which has valuable trees such as ironwood, Burmese ebony, eng, Siamese sal, ingyin, iron wood, Makhaa, Tabak (a kind of Lagerstroemia), and more than 800 kinds of others. And the brackens are many kinds of bamboo, rattan and orchid.
Animals found, and inhabit there, are small-size animal such as pheasant, jungle fowl, barking deer, mouse deer, monkey, wild boar, squirrel, chipmunk and many valuable birds, for examples, white-eyed river-martin--which is now believed it becomes extinct.