This area was designated a park in 1975, becoming Thailand's 13th National Park. It covers an area of about 84 square km. Named after 2 mountains in Chantaburi and Rayong provinces. It provides an important watershed area for the agriculture of the region.

Tropical broad-leaved evergreen forests dominated the lowland elevations up to 1000 m.

There is heavy rain from May to October about 3,000 mm. of rain per year, nicely cold from November to February, and summer from March to April with approximately 26-27 degrees Celsius all the year round.

Animals that can probably still be found in the park include elephant, gaur, serow, bear, wild pig, deer, pileated gibbon and banded langur. There are also 53 confirmed bird species including the wreathed and great hornbills. "In the deep pools of Khao Chamao waterfall is found a species of carp (tor soro) which old timers in the area claim gave the Khao Chamao, which translates to get drunk its name. They say people who eat the fish become light headed. A favourite food of the carp is the fallen fruit of a particular tree growing beside the waterfall. This fruit apparently has a mysterious property which has no visible effect on the carp but seemingly causes intoxication in people who eat the fish. This fruit, intriguingly, is a traditional curative for leprosy." (Gray, Piprell, Graham 1994)