Hiranyakasipu was troubling the Devas as he got a boon from Brahma that no human can kill him, neither could he be killed in morning, noon or night nor in air, water or ground. His son Prahlada was an ardent devotee of Vishnu against the wishes of his father. He also tried to slay Prahalada at various times, just to be saved by the divine grace of Vishnu.
During a heated argument with Prahalada, Hiranyakasipu was asking if Vishnu is present everywhere and went on to break a pillar with his weapon. Vishnu took the avatar of Narasimha and appeared from the pillar. Narasimha was a human with lion face and slayed Hiranyakasipu on an evening time in a doorway, which was neither land nor air.
Ages past by, when Lakshmi, the consort of Vishnu was doing penance at this place. Hanuman (locally called Anjaneyar) was carrying an image made of Saligrama and Lakshmi requested him to get her a view of Vishnu in the form of Narasimha. Hanuman entrusted the saligrama to her and asked her to hold it until he returns.
Lakshmi placed the image at this place, which grew into a mount before Hanuman could return. Narasimha appeared before both of them and set his abode at this place. The Narasimhaswamy temple, located right at the foot hills is also associated with this legend and Hanuman is believed to have worshipped him in standing posture form a distance axial to the temple.