The Kumbh Mela is an event with ancient roots. It is said that the devas--gods--went to Lord Vishnu requesting his help in their endless fight against the asuras, or demons. Lord Vishnu told the gods to churn the ocean and thus obtain the nectar of immortality, known as amrit.
However, the task required that the gods coordinate their efforts with the asuras, and the two sides joined together in the epic event, employing the snake Vasuki as their churning rope. After a great deal of churning, the ocean began to release its contents--at first poisons, and then a variety of treasures, culminating in the release of a pitcher, or kumbh, of amrit.
A struggle ensued between the gods and asuras, during which four drops of the amrit were spilled onto the towns of Allahabad, Haridwar, Ujjain, and Nasik. The Kumbh Mela rotates between each of these towns over a 12-year period. What makes this year's Mela particularly auspicious is that it takes place as the sun enters Aries and Jupiter enters Aquarius, an alignment that occurs only once every 144 years. Millions of pilgrims arrive at the confluence of the Ganga, Yamuna, and Saraswati rivers, where they take a spiritually purifying, physically restorative bath.