Description: This Dhivyadesam is located in Kancheepuram close to the Ashtabhuyakara Dhivya Desam, a mile west of the Varadharaja Perumal Temple. It has been glorified by six of the 12 Azhwars. There are references to shis shrine in tamil sangam works such as Tolkappiam and Silappadikaaram.

The Dhivya Desams revered by the Azhwars in Perumaal Kanchi are Attigiri (the vast Varadharaja Perumal Temple), Ashtabuyakaram, Thiruttankaa, Thiruvelukkai and Thiruvegkaa, while those in Shiva  Kanchi are Thiru Oorakam (Ulagalanda Perumaal Koyil) , Thiru Neeragam, Thiruppaatakam, Nilaattingal Tundam, Thirukkaaragam, Thirukkaarvaanam, Thirukkalvanur, Thiruppavalavannam and Parameswara Vinnagaram. The vast Ekambreswarar Temple(Prithvi Stalam)  revered by the Thevaram hymns, is located in Periya (Shiva) Kanchi, as are the Kamakshiamman and the Kumara Kottam Temples.

Deities: The Moolavar here is Yatotkaari or Yatotkaara Perumaal also known as Sonnavannam Seida Perumaal, in a reclining posture facing East. Thaayaar here is Komalavalli. The 'sayana' posture is reversed here, with the head to the devotee's right, unlike other shrines. Saraswati is also seen in the sanctum.

Legend has it that Poikai Azhwar, among the first of the Azhwars, was discovered on a lotus flower in the Poikai Pushkarini. Legend also  has it that the Vegavati (Saraswati) river, came flowing in spate, to destroy the yagna (ritual) being performed by Bhrama. Upon being implored by the Devas and Bhrama, Perumaal, manifested himself in a reclining position , across the river, damming it. The word Vegavati Anai (dam), is the root of the name Vegkaa. The same legend is told at the Varadharajar Temple too.

Legend has it that a disciple of Thirumazhisai Azhwar transformed an aged woman to a young damsel, so that her services would be available to the Temple for a longer period here. Hearing of this, a Pallava king approached his disciple to have him transform him (the king) into a youthful personality. Upon his refusal, he was banished from the kingdom, and Thirumazhisai Azhwar followed him, leaving Kancheepuram. Perumaal upon hearing the pleas of Thirumazhisai Azhwar, followed him out of Kancheepuram, and upon Perumaal's departure, the entire city became one of darkness. The king requested Azhwar and his disciple to return to the ciity, and Perumaal returned too, and reversed his position in the Temple. The name Sonnavannam seida Perumaal came into being because Perumaal 'listened' to the Azhwar and left the Temple, and again listened to his pleas and returned.  It is believed that PoikaiAzhwar (among the first three Azhwars) was discovered in the Poikai pushkarini in a lotus flower.

This Temple occupies an area of about 4 acres and has two prakarams and a five tiered rajagopuram facing west..  Two worship services are carried out each day here. Vaikuntha ekadasi is celebrated for 22 days in Margazhi. PoikaiAzhwar's birth is celebrated in the month of Aippasi. A golden palanquin is used during festivals here.

Thirumazhisai Azhwar refers to seven shrines featuring Perumaal in a reclining position   - Thirukkudandai, Thiruvegkaa, Thiruvallur, Thiruvarangam, Thiruppernagar, Anbil and Thirupparkadal in a paasuram.