The fourth incarnation of Lord Vishnu, Lord Narasimha, is half human and half lion. Legend says that Narasimha after killing Hiranyakashipu, slew another giant named Jharasura (Jalasura) who was a staunch devotee of Lord Shiva. While breathing his last, Jharasura beseeched Vishnu (or rather, his incarnation) to reside in the cave in which he was living and to grant boons to devotees. Granting last wish of his, Narasimha came to live in the cave. There is a roughly carved image of Narasimha on a stone wall at the end of the cave. After being killed, the demon turned into water and started flowing down the feet of the Lord Narasimha. The flow of water in the cave tunnel is continuous since then. The spring has never dried out.