The headwater of Ganga called the bhagirathi is fed by the hangout glacier and joined by alaknanda at devprayag in uttarakhand. At haridwar the Ganga emerges from mountains on to the Plains. The length of Ganga is over 2500km.ambala is located on the water divide between indus and Ganga river system. The Plains from ambala to sundarbans stretch over 1800km.
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