The place was originally believed to have housed a Shiva temple. A Chola ruler, who was a Saiva fanatic, wanted to demolish the Vishnu temple in his province. Seeing the images of Vinayagar and Dakshinamurthy, which are otherwise found in Shiva temples, he was taken aback. It is believed Vishnu himself appeared before the king to acknowledge the oneness of almighty. Following the legend, the image of the presiding deity holds a lotus, the symbol of Brahma and has a third eye like Shiva, denoting the oneness. The region was called Tiruvaheendrapuram to honour Adisesha, who was originally called Vaheendran. Vaheendra is believed to have propitiated Indra, the king of celestial deities. Tiruvaheendrapuram became Thiruvanthipuram with the passage of time.