Traditions say that Lord Vishnu offered the idol of Sree Poornathrayeesa to Arjuna (the third of the five Pandava brothers), when he sought the help of the Lord to give rebirth to the ten children of a Brahmin. The ten children and the sacred idol were taken by Arjuna in his chariot and he handed over the children to the Brahmin. In memory of this event, a temple was built with a sanctum-sanctorum in the form of a chariot. Lord Ganesh was sent by Arjuna to search a holy place for the installation of Lord Vishnu. Earlier, the idol was kept in a palace which is situated at the west of the main temple and now it is known as Poonithura Kottaram.