One of the designated World Heritage Sites of UNESCO, the Sunderban Delta is formed by three popular rivers namely Ganges, Brahmaputra and Meghna. This mangrove-dominated delta comprises of complex ecosystem. The Sunderban Delta lies between two countries – Bangladesh and India. Although, the major portion (62%) of the delta is situated in Bangladesh. The Sunderban delta meets the Bay of Bengal in the south and Baleswar River in the east. In the north the delta forms a sharp interface with thoroughly cultivated land.

About 200 years back, the Sunderbans measured about 16,700 km which has been drastically reduced to 4,143 km. Around 1,874 km comprises of rivers, streams and canals. The region is considered to be the meeting place of Bay of Bengal's salt water and Ganges's freshwater.

The Sunderbans delta has been formed by the natural deposition of upstream sediments and inter-tidal segregation. The region also encompasses numerous drainage lines along with surface and subaqueous levees, splays and tidal flats.

During the monsoon season a major portion of the Delta gets submerged. Due to which, the people living in the Ganges has to face lot of challenges. The Sunderban Delta also consists of marginal marshes which lies above the tidal channels. The floor of Sunderban's that lies above the sea level ranges from 0.9m to 2.11m.

Even the Biotic life in the region plays an important role during the coastal evolution. The place has developed a variety of wildlife habitat like beaches, estuaries, swamps, coastal dunes, levees, tidal creeks and tidal flats. Swamp morphology plays an important role in the development of new landmass and inter-tidal vegetation. Most of the India's exotic tigers reside on the Sunderban's forest – biggest delta in the world. More than 300 Royal Bengal Tiger reside on this portion of Sunderban forest.