Rathnagirinathar temple at ancient Rathinagiri, which is currently called as Iyermalai or Ayyarmalai or Aivar Malai is located at about far from Kulithalai, southerly. This is the first Padal petra sthalam in the region. The Ratnagireeeswarar temple is built on a hillock reached by a flight of 1000+ steps while the Sivapureeswarar temple is at the foothills level. The idols of Siva and Ambal face each other in the Upadesa posture in the temple. A legend has it that Indra, Surya, Adi Sesha, Durga, Agasthya Muni and the Sapta Matas have worshipped the presiding deity at this kshetram.