Authorities in India are racing against time to get the city of Prayagraj ready to host the Hindu festival Kumbh Mela, described as humanity's biggest gathering. About 400 million pilgrims are expected to attend the 45-day spectacle, which is so large it can be seen from space.

A six-week Maha Kumbh Mela or Great Pitcher Festival begins in India on Monday, a Hindu sacred event that will be the world's largest gathering of humanity as it showcases religion, spirituality, tourism and crowd management.

The world's largest gathering of humanity begins in India on Monday with the opening of the Kumbh Mela, a six-week Hindu festival.

Over 6 weeks from January 13, 350-400 million Hindu pilgrims will converge on the Ganges. Many will bathe in its waters to achieve salvation The world's largest gathering of humanity begins in India on January 13 with the opening of the Kumbh Mela,

The Maha Kumbh Mela, or the Great Pitcher Festival, will bring more than 400 million people to Prayagraj city in northern India over a period of six weeks starting Monday, making it the largest gathering of humanity in the world.