Oondreswarar temple is located in a village called Poondi, around from Thiruvallur on the Thiruvallur - Thiruthani road. The temple has a flat entrance tower facing South, and all the shrines of the temple are enclosed in concentric rectangular granite walls. The central shrine is approached through the side doors facing North axial to the gateway tower to the Minnoli Amman shrine. The central shrine facing East houses the image of Oondreswarar in the form of Lingam. The shrine of Minnoli Amman, facing South has a gopuram type roof. The central shrine is approached through a Mahamandapam and Arthamandapam. As in other Shiva temples in Tamil Nadu, the shrines of Vinayaka, Murugan, Navagraha, Chandekeswara and Durga are located around the precinct of the main shrine. The second precinct has a shrine of Vinayaka and a garden around the periphery of the compound wall.