Duration of fair is around one Month, but apart from government stall, it runs around two month. Originally, the venue of the fair was Hajipur which situate across river Gandak(Narayani) and only the performance of the puja used to take place at the Harihar Nath temple of Sonepur. However, under the rule of the Mughal Emperor Aurangzeb, the venue of the fair got shifted to Sonepur. The temple of H
arihar Nath is believed to have been originally built by Lord Rama, on his way to the court of King Janak to win the hand of Mata Sita. It is further said that Raja Man Singh later got the temple repaired. The Harihar Nath temple, as it stands today, was built by Raja Ram Narain, an influential person during the late Mughal period
