Piranmalai is said to have been ruled by Paari Vallal. Piraanmalai is said to be a block of Mount Meru, which got blown off during a fierce tussle between the serpent king Aadiseshan and the wind God Vaayu(as in Tiruchengode). Since this hill is in the form of a Sivalingam, it is also called Prachandragiri and Katoragiri. Bhrama, Saraswati, Subramanya and Nandi are believed to have worshipped Shiva here. Shiva is believed to have revealed a vision of his marriage with Parvati to Agasthya Muni here. Lord Shiva in this hill temple is known as Mangaibaagar(also called MangaiNayagar) and Goddess Parvati is known as Thenammal. In this hill, there is a natural stone carving that depicts the marriage of Lord Shiva and Goddess Parvati . It shows Lord Mangaibaagar is holding hands with Goddesss Thenammal .