The Indian Sundarbans are best understood from the water. Here the Ganges–Brahmaputra delta breaks into tidal rivers, creeks, mudbanks and mangrove islands in West Bengal. The UNESCO-listed Sundarbans National Park covers 133,010 hectares, a protected part of a much larger cross-border ecosystem shared with Bangladesh. The distinction matters: figures for the entire Sundarbans should not be presented as the area of this Indian park. A visit is not a conventional walk through forest trails. Inside the reserve, the official Tiger Reserve describes launches and boats as the means of movement, so the landscape is experienced from a regulated river route.
UNESCO describes the wider Sundarbans as about 10,000 square kilometres of land and water, with more than half in India and the rest in Bangladesh. Its channels are shaped by tides, sediment, monsoon rainfall and the meeting of river and sea. Banks erode in some places while silt accumulates in others; islands and waterways are not static scenery. Mangrove roots help stabilize shorelines, trap sediment and create nursery habitat for aquatic life. This physical process is part of the attraction, but it also explains why access, routes and settlements can be affected by weather and changing water conditions.