According to Hindu mythology, the Kumbh Mela celebrates the victory of gods over demons in a furious battle over nectar that would give them immortality. As one of the gods fled with a pitcher of the nectar across the skies, it spilled on four Indian towns: Allahabad, Nasik, Ujjain and Haridwar.
The Kumbh Mela is held four times every 12 years in those towns. Hindus believe that sins accumulated in past and current lives require them to continue the cycle of death and rebirth until they are cleansed. If they bathe at the Ganges on the most auspicious day of the festival, believers say they can rid themselves of their sins.
Associated Press writer Biswajeet Banerjee contributed to this report.