Sundarbans (pronounced / s ʌ n ˈ d ɑːr b ə n z / ) is a mangrove area in the delta formed by the confluence of the Ganges , Brahmaputra and Meghna Rivers in the Bay of Bengal . Spread across parts of India and Bangladesh , this forest is the largest mangrove forest in the world. [ 6 ] It spans the area from the Baleswar River in Bangladesh 's division of Khulna to the Hooghly River in India 's state of West Bengal . It comprises closed and open mangrove forests , land used for agricultural purpose, mudflats and barren land, and is intersected by multiple tidal streams and channels. Sundarbans is home to the world's largest area of mangrove forests. [ 7 ] Four protected areas in the Sundarbans are enlisted as UNESCO World Heritage Sites , viz. Sundarbans...