The Kumbh Mela festival, the largest religious gathering in the world, has begun in the northern Indian city of Prayagraj.

Days before India started its mammoth Kumbh Mela festival, a video showing preparations for a nighttime light show surfaced in social media posts that falsely linked it to the six-week Hindu event. The video was in fact originally published by a US-based drone show company and shows a Christmas celebration.

India began on Monday its Maha Kumbh Mela, or Great Pitcher Festival, which is expected to draw more than 400 million visitors to the northern city of Prayagraj over six weeks, making for the largest gathering of humanity in the world.

An estimated 40 crore people are expected to attend the Maha Kumbh in Prayagraj this year with the Uttar Pradesh government earmarking a budget of Rs 6,990 crore for the gathering.

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.

Organisers of India's Kumbh Mela have prepared to host a staggering 400 million devotees at the six-week Hindu festival that starts Monday and is expected to be the largest human gathering in history.