Kumbh Mela

Kumbh Mela is a Hindu festival held every three years in which the faithful wash themselves in one of four rivers sacred to Hinduism -- the Ganges, Yamuna, Godavari, and Shipra. Each Kumbh Mela involves visiting that cycle's river at a specific festival site, so each site and river is visited once every twelve years. (Actually, there are also "half" festivals and the Yamuna is visited where it joins the Ganges and, supposedly, the Sarasavati -- the collection of the three rivers known as the "Triveri Sangam" -- so some of the rivers are visited more than once.)

This year is the Maha Kumbh Mela ("maha" means "great") in Allahabad (also known as Prayag, its Hindu name; "Allahabad," the name given by the Muslim Mughal Emperor Akbar in 1583, means ~"City of God" using the Arabic for "god"), which is the location of the Triveri Sangam. It's a big deal, supposedly the largest gathering of people on Earth. The Boston Globe's photo site The Big Picture has a spread on it, and here are a few of the images: