In Skanda Puran, Maheshwar Khand, All the sages residing in Naimisharanya asked Sutji about the manifestation of Arunachala lingam . So Sage Sutji described how Arunachala lingam came into existence.
Arunachala Lingam came into existence
once Lord Vishnu and Brahma witnessed an effulgent Pillar. It had manifested from
nowhere and was limitless in size. It’s radiance put the whole world ablaze. Both of them worshiped that marvelous pillar. Actually, that effulgent pillar was a Shivalingam. Lord Shiva manifested from it after being pleased by their devotion. they both requested him to minimize his size and establish himself in the form of Arunachala Shivalingam.
Lord Shiva agreed to minimize his size as well as his effulgence by establishing himself in the form of ‘Arunachaleshwar Lingam’.The holy place of Arunachaleshwar remains untouched while the whole world gets submerged in water at the time of deluge. The place where Arunachala Lingam located is in Thiruvannamalai in Tamil Nadu.