The Ganga is formed in Uttarakhand where two Himalayan rivers, the Bhagirathi (the source in Hindu tradition) and the Alaknanda (the longer source stream), meet at one of the five 'prayags'. It leaves the hills at Rishikesh, enters the plains at Haridwar, and flows through Uttar Pradesh, Bihar and West Bengal. Its biggest tributary is the Yamuna; others include the Ghaghara, Gandak and Kosi.
Key facts
- The Bhagirathi and Alaknanda meet in Uttarakhand to form the main stem; it is India's longest river.
- Enters the plains at Haridwar; splits near Farakka, where the Hooghly branches off; called the Padma in Bangladesh.
- The Ganges delta is the world's largest, about 64,000 sq km.
- The Alaknanda is the hydrological source (longer); the Bhagirathi the traditional one.
Why exams ask about it
The glacier, the confluence town, where the Yamuna joins and the delta are the usual questions.