The fortnight - long Pitrapaksh period, considered by the Hindus as auspicious for offering 'pindadan' - - religious service seeking salvation for the dead from the cycle of rebirth, began in Bihar's Gaya town on Thursday.
District Magistrate Kumar Ravi said nearly a million pilgrims were likely to visit Gaya to offer pindadan for which the administration has made elaborate arrangements.
"The administration has decided to run e - rickshaws for the elderly pilgrims, " said Ravi.
The pindadan sees thousands of Hindus from across India and even abroad gather at Gaya, about 100 km from state capital Patna.
Pindadan is traditionally offered on the banks of the Falgu river during the 15 days of the waning moon of the Hindu month Ashwin.
This year, it extends from Septemnber 15 - 30.
According to Hindu belief, the soul wanders after death until pindadan is performed.
"The soul keeps wandering till this ritual is performed by male descendants of the dead, " said priest Murari Lal.
It is mandatory for the devotees offering pindadan to tonsure their head, take a holy dip and head for the Baitarni pond.
Some rituals are conducted in the Falgu river nearby.
The prayers are performed at the famous Vishnupad temple named after Hindu god Vishnu.
Priests, known as Gaywal - pandas, conduct the ritual.
The festival was officially inaugurated on Sunday by Bihar assembly speaker Uday Narayan Choudhary at the temple.
Legend has it that Lord Rama and his wife Sita performed this religious rite for his father, King Dasharath.