Ganges (gănˈjēz) [key] or Ganga gŭngˈgä, river, c.1,560 mi (2,510 km) long, rising in the Gangotri glacier in the Himalayas in Uttarakhand state, India, and flowing generally southeast through NE India across a vast plain to the Bay of Bengal in Bangladesh; the most sacred river of Hindu India. The fertile Ganges plain is one of the world's most densely populated regions; rice, grains, oilseed, sugarcane, and cotton are the main crops. Because of its location near major population centers, however, the river is highly polluted.
The upper Ganges supplies water to extensive irrigation works. The river passes the holy bathing sites at Haridwar, Allahabad (where the Yamuna River enters the Ganges), and Varanasi. Below Allahabad the Ganges becomes a slow, meandering stream with shifting channels.
The lower Ganges is joined by the Brahmaputra River W of Dhaka, Bangladesh, to form the Padma, its main channel to the sea. The united rivers branch into many distributaries, forming the vast and fertile Ganges-Brahmaputra Delta, which stretches from the Hugli River on the west to the Meghna on the east. The delta region covers roughly 25% of India's total territory and supports upwards of 300 million people. The delta's southern fringe, a great wilderness of swamp, dense timber forest, small islands, and tidal creeks, is known as the Sundarbans; it has been the site of land reclamation projects. This low-lying area has repeatedly suffered great devastation from cyclones and coastal flooding. Kolkata, India, and Chittagong, Bangladesh, are the delta's main seaports.