The king made Sekkizhaar his minister at his capital. Sekkizhaar was an ardent devotee of Lord Shiva and was regularly worshipping Lord Shiva at Thirunaageswaram near Kumbakonam. During later stages, Sekkizhaar built a temple for Lord Shiva at Kunrathur which is very similar to the Thirunaageswaram temple. He installed the deity (Shiva Lingam) with Naagaabaranam (snake as an ornament) around the Shiva Lingam and named the Lord as Sri Naageswarar.
This is considered as the Raagu sthalam for the Navagraha worship and was built by the descendents of Sekkizhaar (who wrote Periya Puranam). Here the Nagabharanam around the linga is supposed to be the Rahu for worship. This place is also called as Vada Thirunageswaram. The temple and its tank are clean and well maintained.