Kumbh Mela is a Hindu pilgrimage that occurs four times every 12 years and rotates among four locations: Prayag (Allahabad), Haridwar, Ujjain and Nashik. Each 12-year cycle includes one Maha Kumbh Mela (Great Kumbh Mela) at Prayag, which is attended by millions of people, making it the largest gathering anywhere in the world. Kumbh Mela produces a temporary city that has proper quarters, infrastructure and services.
The major event of this festival is a ritual bath at the banks of the rivers in each town. Other activities include religious discussions, devotional singing, mass feeding of holy men and women and the poor, and religious assemblies where doctrines are debated and standardized. The Maha Kumbh Mela is the most sacred of all the pilgrimages. Thousands of holy men and women (monks, saints and sadhus) attend, and the auspiciousness of the festival is in part attributable to this. More recently, the event has tended to attract a lot of western tourists too.