Wanderlust World Wanderlust World The Ganges River's primary source is the Bhagirathi River, which originates at the Gangotri Glacier (Gaumukh, "Cow's Mouth") in the Garhwal Himalayas of Uttarakhand, India, at approximately 3,892 m (12,769 ft) elevation (not 7,000 m—the glacier terminus is lower; the peaks above reach 6,000–7,000 m).
The Bhagirathi flows ~205 km before meeting the Alaknanda River at Devprayag. From this confluence, the river is officially named the Ganges (Ganga). The Alaknanda, fed by the Satopanth and Bhagirath Kharak glaciers, is hydrologically larger at the confluence, but Hindu tradition designates the Bhagirathi as the source stream.
Hindu cosmology holds that King Bhagiratha's penance brought Ganga from heaven to earth, caught in Shiva's matted locks to soften her descent—the glacier's icy cave evokes this imagery. Hydrologically, the Gangotri Glacier (30 km long, 2–4 km wide) is retreating ~20 m/year due to climate change, threatening long-term flow.
From Devprayag, the Ganges flows 2,525 km through the Gangetic Plain—Haridwar, Kanpur, Prayagraj (Sangam with Yamuna), Varanasi, Patna—into Bangladesh (as Padma), merging with Brahmaputra (Jamuna) and Meghna to form the vast Ganges-Brahmaputra Delta, emptying into the Bay of Bengal.