Hollongapar Gibbon Wildlife Sanctuary is a small sanctuary, covering an area of around 20.98 sq. km. The sanctuary is named so as it is a habitat of the hoolock gibbon, the only ape species found in India. It has semi-evergreen forests and evergreen patches of tea gardens and offers shelter to varied flora and fauna.
The sanctuary is home to various mammals, including elephants, tigers, leopards, Assamese macaques, pig tailed macaques, capped langurs and jungle cats. The Indian civet, giant squirrel, sambar, wild pigs and barking deer can also be spotted inside the sanctuary.
The sanctuary is inhabited by various resident as well as migratory birds, such as the Indian pied hornbill, hill myna, osprey and kalij pheasant. Various species of reptiles found in the sanctuary include the Indian tent turtle, Indian python, common monitor lizard and Indian cobra.