Akshaya Vat
संगम सिंहासन सुठि सोहा। छत्रु अक्षयवटु मुनि मन मोहा।।

According to a legend, once the sage Markandeya asked Lord Narayana to show him a specimen of the divine power. Narayana flooded the entire world for a moment, during which only the Akshayavat could be seen above the water level.
A sacred fig tree located within the Patalpuri Temple at the Allahabad Fort is worshipped as the Akshayavat by some Hindus. As of 2011, a permission from the Commandant of Allahabad Fort's Ordnance Depot is needed to visit this tree. A sacred fig tree located within the Patalpuri Temple at the Allahabad Fort is worshipped as the Akshayavat by some Hindus. As of 2011, a permission from the Commandant of Allahabad Fort's Ordnance Depot is needed to visit this tree. On one day during the Kumbh Mela, the site is open to all the pilgrims. According to the local belief, the sage Shukdeva narrated Srimad Bhagavatam to the king Parikshit under this tree.in Mamaidev"s sacred scripture, Akshay vat is also known as Prayag vat, the Mamaidev a great philosopher and predictor in 13th century,He described Sacred Akshay vat in his Holy scripture. The Mamaidev preached to millions birds of Akshay vat.Prayag vat is the safe home of the millions Birds,where birds are making their nests and starting their new lives, and born at Prayag vat,which is Immortal tree at bank of 3 river connected.

Patalpuri Temple

Patalpuri Temple and Akshaya Vat, both are located inside the Allahabad Fort. Patalpuri Temple, the underground temple is also one of the oldest temples in India. According to a legend it is believed that Lord Rama performed the panda daan for his forefathers in this temple. In addition, the temple also has a special mention in the travelogue of the Hiuen Tsang, a Chinese traveller who visited India in AD 644.