4. Sunderbans National Park
Besides being a national park, this place is also a tiger and biosphere reserve, located in West Bengal. The national park is covered with mangrove forests and is one of the largest reserves of the Bengal tiger in India. One can spot a variety of birds and the salt-water crocodile in this park. The best part about this park is that the only way to roam about the territory is by boats. The best time to visit is from December to February.