The city of Prayāga is situated a few miles from the city of Allahabad. The name Prayāga is given due to successful sacrifices performed there. It is said: prakṛṣṭaḥ yāgaḥ yāga-phalaṁ yasmāt. If one performs sacrifices at Prayāga, he certainly gets immediate results without difficulty. Prayāga is also called Tīrtharāja, the king of all places of pilgrimage. This holy place is situated on the confluence of the Rivers Ganges and Yamunā. Every year a fair takes place there known as Māgha-melā, and every twelve years a Kumbha-melā is also held. In any case, many people come to bathe there every year. During Māgha-melā, people from the local district generally come, and during Kumbha-melā people come from all over India to live there and bathe in the Ganges and Yamunā. Whoever goes there immediately feels the place’s spiritual influence. A fort located there was constructed by the Emperor Akbar about five hundred years ago, and near the fort is a place called Triveṇī. On the other side of Prayāga is an old place known as Pratiṣṭhāna-pura. It is also well known as Jhuṅsi. Many saintly people live there, and consequently it is very attractive from the spiritual point of view.
Bathing during the month of Māgha at Māgha-melā still takes place. This has been a very old melā (assembly) from time immemorial. It is said that the Lord in the form of Mohinī took a bucket of nectar and kept it at Prayāga. Consequently Māgha-melā has been observed, and there is an assembly of holy men there every year. Every twelfth year there is a Kumbha-melā, a great festival, and all the holy men from all over India assemble there.
Ref >> Srila Prabhupada Vani.