Every 12 years, the Kumbh Mela, a centuries-old Hindu pilgrimage, temporarily transforms an empty floodplain in India into one of the biggest cities in the world.

Seth Dixon, Ph.D.‘s insight:

Hindu pilgrims from all over India flock to bathe where it the Yamuna Saraswati Rivers join with the Ganges River for a religious experience.  This is a massive undertaking where the cultural practices create migratory patterns that reshape cities because of a sacred physical geography

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