One such Triveni Sangam, in Prayag (Allahabad) has two physical rivers Ganges, Yamuna, and the invisible or mythic Saraswati River. The site is in Prayag, India. A place of religious importance and the site for historic Kumbh Mela held every 12 years, over the years it has also been the site of immersion of ashes of several national leaders, including Mahatma Gandhi in 1948 The three rivers maintain their identity and are visibly different as they merge. While the Yamuna is deep but calm and greenish in colour, the Ganga is shallow, but forceful and clear. The Saraswati remains hidden, but the faithful believe that she makes her presence felt underwater. During the monsoon, when the rivers are in full flow, the confluence of the rivers is seen clearly due to the force of the water, but the same force makes having a dip at the confluence difficult. While the Ganges is only 4 feet deep, the Yamuna is 40 feet deep near the point of their nexus. The river Yamuna merges into the Ganges at this point and the Ganges continues on until it meets the sea at the Bay of Bengal. At the confluence of these two great Indian rivers, where the invisible Saraswati conjoins them, many tirtha yatris take boats to bathe from platforms erected in the Sangam. This, together with the migratory birds give a picturesque look to the river during the Kumbha Mela, in the month of January. It is believed that all the gods come in human form to take a dip at the sangam and expiate their sins. (Wikipedia)