The Ream National Park is one of the seven National Parks in Cambodia, established in 1993 when the Cambodian government began to take action to protect many of its threatened areas.

 It encompasses 210 km² divided to 15,000 hectares of land and 6,000 hectares of marine habitat. The national park contains beaches, mangrove forests, tropical jungles and over 150 species of bird including a few threatened species and is well noted for its monkey population. Uninhabited Koh Sess island is located at the southeastern end of the park.
Boat trips on the river and through the mangrove channels are offered, then into the Gulf of Thailand ocean.
The park offers walking tours of the mountain, safari tours of the smaller mammals and birds and waterfalls.
Wat Ream, a Buddhist temple, is also worth a trip.