Why is Gaya specifically chosen for Pind Daan above all other tirthas?

Gaya is chosen because of its direct scriptural endorsement in the Vayu Purana, Agni Purana, Vishnu Purana, and the Mahabharata — all of which declare Gaya as the supreme Pitru Tirtha. The Vishnupad Temple in Gaya marks the exact spot where Lord Vishnu placed his foot on the chest of Gayasura (the asura who allowed Vishnu to do so as penance), leaving a permanent footprint. This makes Gaya the one place in India where Vishnu is believed to be physically present specifically for accepting ancestral offerings. The Vayu Purana states that a single Pind Daan at Gaya liberates seven generations of ancestors (Sapta Pitri) — no other tirtha carries this promise. Additionally, the Phalgu River at Gaya is believed to carry offerings directly to Pitru Loka.