T he small village of Siddharkadu, not too far from Poonamallee, is a historic place and home to a few temples, one being a Vishnu shrine dedicated to Sundararaja Perumal. Siddharkadu is said to derive its name from a dense forest where Siddhas (spiritual people) practiced yoga and meditation. There are numerous sculptures of Siddhas found in the temples here. The entrance to the temple is via five-tier gopuram. Visitors can notice two stone sculptures of women personifying the river goddesses Ganga and Yamuna, adorning the sides of the gopuram. On the lintel of the doorway of the large mandapam in front of the central sanctum-sanctorum (garbha-griha), is a small but well-wrought carving of Vishnu as Anantashayee with rishis and divine musicians on either side.
The main image of Sundararaja Perumal, flanked by consorts Sri Devi and Bhu Devi, is in a standing posture, while the processional image (utsava-murti) is a replica of the main deity. Also seen in the central sanctum are the stone and processional images of Krishna in a dance pose. Nearby are the stone images of some Azhvars (important devotees of Vishnu, totally 12 in number) like Nammazhvar, Thirumazhisai Azhvar (who hailed from the nearby village of Thirumazhisai) and Thirumangai Azhvar and also Ramanujacharya, the pre-eminent Vaishnava preceptor (Acharya).
An important feature of this temple is that 16 images of Narasimha, such as Yoga Narasimha, Ugra Narasimha and Lakshmi Narasimha, have been carved on the pillars of the numerous mandapas. There are sanctums for Goddess Lakshmi worshipped as Sundaravalli Thayar and Andal. One particular Siddha connected with this temple is revered as Garudakodi Siddha and his image is sculpted on one of the pillars of the mandapa of the Andal shrine.