This ancient architectural wonder has many rooms built for courtiers and royal families and adorned with some precious jewels. The main attraction is the 6.5 square meter stupa built by the Ajatashatru. Everywhere, and again, the corners are worth a visit. Another feature of the Ajatashatru Fortress is the Bimbisara Prison, named after King Bimbisara, the father of the Ajatashatru. King Bimbisara was imprisoned in this prison for his zealous dedication to the Buddha. There was also a secret tunnel under the fortress, but its depth is unknown due to its devastation. Here you can take pictures and record the well-preserved history of the fortress. It is attractive to many history lovers and scholars.