Patalpuri temple, one of the oldest and most famous temples in India, is an underground temple contained by the Allahabad fort. It is believed that lord Rama has visited this temple. And a famous Chinese traveler and writer Huan Tsang also visited it. The undying banyan tree or 'Akshayavat' within the Patalpuri temple has found state in the account of several ancient scriptures, writers and historians. The pilgrims used to throw themselves from this tree to achieve salvation.
This place of worship inside the Fort is an important place of pilgrimage. It dates from the epic age. Hiuen Tsang, the Chinese traveler who visited the Fort in 634 AD during his journey through India, mentioned its imprinted stone divinity. It became an underground holy place when Akbar construct his Fort over and around in 1583.