Starting Tuesday, tens of millions of Hindu devotees in India will gather to wash their sins away on the banks of the Ganges River in a festival known as the Kumbh Mela. The tradition, which dates back over a millennia, is billed as the world's largest gathering of humanity. Through March 4, an estimated 120 million people will flock to the northern city of Prayagraj to bathe at the Sangam, a confluence of the Ganges, the Yamuna and the Saraswati rivers, BBC reports. By comparison, that’s almost 14 times the population of New York City
http://time.com/5501801/india-kumbh-mela-2019/
How to plan a festival for 100m people
https://www.bbc.com/news/world-asia-india-46834335
Wherein both will be those (maidens) restraining their glances upon their husbands, whom no man or jinn yatmithhunna (has opened their hymens with sexual intercourse) before them (Quran 55:56, Mushin)