Vishnupada Mandir is a 220 year old temple in Gaya in Bihar.
The temple is dedicated to Lord Vishnu and is located along the Falgu River.
Many saints like Ramanujacharya, Madhvacharya, Sankaradeva and Chaitanya Mahaprabhu have visited this shrine.
There is a 40 cm long footprint of Lord Vishnu inside Vishnupada Mandir.
Web : http://en.wikipedia.org/wiki/Vishnupad_Mandir