By Saurabh Sharma PRAYAGRAJ, India (Reuters) -Naked Hindu ascetics smeared in holy ash charged into the waters of sacred rivers in India on Tuesday, part of a large crowd of 35 million devotees who took the holy dip on the second day of the Maha Kumbh Mela,

NEW DELHI (Reuters) - India's Maha Kumbh Mela, or Great Pitcher Festival, is set to be the world's largest gathering of humanity, with 400 million visitors expected at the six-week event that began this week in the northern city of Prayagraj.

Over the coming 45 days, an estimated 400 million Hindus are expected to come together for Maha Kumbh Mela. The festival is held every 12 years but the "Maha" or grand Kumbh Mela takes place only every 144 years, "marking the 12th Kumbh Mela and a special celestial alignment of the sun, moon and Jupiter", said The Guardian.