2-4 days it depend on how much time to visit sundarban if you are going to sundarban national park for first time will recommended you should plan atleast do sundarban tour package for 1 night 2 days you need minimum 2 day for sundarban. The best way to look out for the wildlife is to take a boat cruise inside the wilderness around the mega fauna bengal tiger (panthera tigris) is the flagship species of sundarban the amazing adaptability of tiger. Sundarban is famous for its tiger it happen to be the only mangrove tiger habitat of the world. Sundarban is the ulimate land of the tiger a swamp forest. Sundarban jungle it lovely landscape world famous mangroves, mangrove adapted wildlife and of course it rich avifauna specially the colourful kingfishers birds.