The Sunderban National Park is a National Park, tiger reserve, and a Biosphere Reserve in the Sunderban delta. It is in the Indian state of West Bengal. This area is densely covered by mangrove forests. It is one of the largest reserves for the Bengal tiger. It is also home to a variety of bird, reptile and invertebrate species, including the salt-water crocodile. On May 4, 1984 it was made a National Park.