Kumbh Mela is a mass Hindu pilgrimage of faith in which Hindus gather to bathe in a sacred river. It is considered to be the largest peaceful gathering in the world where around 100 million people were expected to visit during the Maha Kumbh Mela in 2013 in Allahabad. It is held every third year at one of the four places by rotation: Haridwar, Allahabad (Prayaga), Nashik and Ujjain. Thus the Kumbh Mela is held at each of these four places every twelfth year. Ardha ("Half") Kumbh Mela is held at only two places, Haridwar and Allahabad, every sixth year. The rivers at these four places are: the Ganges (Ganga) at Haridwar, the confluence (Sangam) of the Ganges and the Yamuna and the mythical Saraswati at Allahabad, the Godawari at Nashik, and the Shipra at Ujjain. The name Kumbh Mela comes from Hindi, and in the original Sanskrit and other Indian languages it is more often known as Kumbha Mela. Kumbha means a pitcher and Mela means fair in Sanskrit. The pilgrimage is held for about one and a half months at each of these four places where it is believed in Hinduism that drops of nectar fell from the kumbha carried by gods after the sea was churned. Bathing in these rivers is thought to cleanse one of all sins. The festival is billed as the "world’s largest congregation of religious pilgrims". There is no precise method of ascertaining the number of pilgrims, and the estimates of the number of pilgrims bathing on the most auspicious day may vary; approximately 80 million people attended on 14 February 2013.
The observance of Kumbha Mela is based upon the following story : thousands of years ago, perhaps in the Vedic period, gods and demons made a temporary agreement to work together in obtaining amrita (the nectar of immortality) from the Milky Ocean, and to share this equally. However, when the Kumbha (pot) containing the amrita appeared, the demons ran away with the pot and were chased by the gods. For twelve days and twelve nights (equivalent to twelve human years) the gods and demons fought in the sky for the possession of this pot of amrita. It is said that during the battle, drops of amrita fell on to four places : Prayag, Haridwar, Ujjain and Nasik. Thus, Kumbha mela is observed at these four locations where the nectar fell.
Kumbha Mela is attended by millions of people on a single day. A ritual bath at a predetermined time and place is the major event of this festival. Other activities include religious discussions, devotional singing, mass feeding of holy men/women and the poor, and religious assemblies where doctrines are debated and standardized. Kumbha Mela (especially the Maha Kumbha Mela) is the most sacred of all the Hindu pilgrimages. Thousands of holy men/women (monks, saints, sadhus) grace the occasion by their presence. The suspiciousness of Kumbha Mela is in part attributed to the gathering of thousands of holy men/women at one place on earth
According to astrologers, the 'Kumbh Fair' takes place when the planet Jupiter enters Aquarius and the Sun enters Aries.