It is the most popular National Park of Nepal and the richest wildlife reserve in Asia, situated in the lowland Terai with an area of 932 sq. km. This park includes areas of the Siwalik range covered by dense Sal forest and carpeted with grass, savannah and riverine vegetation. The park is the home to more than 450 endangered Asian one- horned rhinoceros and harbours one of the largest populations of the exclusive and rare Royal Bengal tiger. Besides, there are 4 species of deer, leopards, langurs, sloth bears, wild boars, rhesus monkeys and wild dogs. Gharial and marsh mugger crocodiles are also found in the river water. The unique birds which number over 450 species include cormorants, egrets, storks, geese, jungle fowl, kingfishers along with some endangered species such as Bengal florician, Lesser florician etc. This makes the park a true birdwatcher’s paradise.