What’s billed as the largest single gathering of humanity is taking place right now in the northern Indian city of Allahabad. At the confluence of the Yamuna, Ganges and (mythical) Saraswati Rivers, as many as 100 million people will participate over the next month in an ancient Hindu festival known as the Kumbh Mela. The pilgrimage, which dates back millennia, occurs in 12-year cycles — in 2001, the Indian government estimated a staggering 70 million congregated by the Ganges’ banks to ritually bathe in its sacred waters.

News-agency photographers, of course, have a field day (or month) during the Kumbh Mela. It’s a time when India’s rising global clout and simmering social tensions take a backseat to images of ascetic sadhus — their faces doused in ash, their feral, matted hair coiled like serpents upon their heads — charging the river in religious ecstasy. Of course, it’s nothing new…