The Ajatashatru Fort, as the name implies, was built by King
Ajatashatru of Magadha to strengthen the defenses of his capital Rajagriha (presently,
Rajgir). The ruins of this fort, built on the
Ganges in the sixth century BC, can be seen on the road to
Nalanda, in
Patna District,
Bihar, about 6 km from
Rajgir Railway Station.
The Ajatashatru Fort is built with blocks of rock at a height of 1.5 to 4 m. 32 large and 64 small gates provide access into the fort. This is historically an interesting spot because Ajatashatru had imprisoned his father Bimbisara here.