This is a park at the altitude of 3,000-5,000 ft was opened in January 1976 and covers an area of 68 sq. kms Its main feature is the confluence of Tana and Thiba Rivers and Kaburu and Masinga hydro-electric dams.
There is a vast population of elephants in the park. Other game includes buffalo, impala, hippo, baboon, vervet and Sykes monkeys, warthog, bushbuck, waterbuck, hartebeest, lesser kudu and jackal. Crocodiles are also found in the dams and the rivers. Mwea National Reserve has two picnic sites: Gichuki Island and Hippo Point this park is 180 kms from Nairobi.