The story of Maha Kumbh Mela that is held in Prayag (Allahabad), Haridwar, Ujjain and Nashik is associated with the Samudra Manthan or churning of the ocean mentioned in scriptures like Bhagavad Purana, Vishnu Purana, the Mahabharata, the Ramayana and numerous other Hindu scriptures.
Legend has it that churning of ocean by Devas (demi Gods) and Danavas (Demons) yielded a jar (Kumbh) full of Amrit (nectar). Devas did not wish to share it with demons.
At the instance of Lord Indra, the King of Devas, his son Jayanta tried to run away with the jar but he was followed by some of the demons.
During the struggle for its possession, a few drops of the nectar dropped at four places corresponding with Haridwar, Prayag, Ujjain and Nasik on the earth. The drops of nectar fell in the rivers here. Kumbh is held at each of the four places namely Haridwar, Allahabad, Nasik and Ujjain once every 12 years.
Millions of devotees come to take a bath in the holy Rivers to wash off their sins. The devotees believe this to be an opportunity to get ‘moksha’ (salvation) and put an end to the never-ending cycle of birth-death-birth.