Why devotees come here
Devanathaswamy temple stands in Thiruvanthipuram, a village on the outskirts of Cuddalore in Tamil Nadu. It is dedicated to Vishnu and is one of the 108 Divya Desams. It is also the only historical temple in South India to house an image of Hayagriva.
Legend says Vishnu appeared here to Adishesha, the serpent that is his mount, to the sage Markandeya, and to Indra. Indra performed a Vaishnava yagna at this place to win the Vajrayudha, the weapon he needed to defeat the demon Vritasura. The Divya Prabandha book counts the temple among the 108 Vishnu temples it praises.
The temple in its current form is believed to date from the Medieval Cholas. The Pandyas, Hoysalas and Vijayanagara rulers added to it later. The Epigraphical Department has found more than 50 inscriptions from the Medieval Chola period here. The temple is built in the Dravidian style of architecture.
Hayagriva is one of Vishnu's avatars, shown with a horse's face. This temple holds an image of him, and it is the only historical temple in South India to do so.

In the appChamundeshwari Temple, MysuruChamundi Hill, Mysuru, Karnataka
In the appDakshineswar Kali Temple, KolkataDakshineswar, North 24 Parganas, near Kolkata, West Bengal
In the appShirdi Sai Baba Temple, MaharashtraShirdi, Rahata taluka, Ahilyanagar district, Maharashtra
In the appAvanti Parshwanath Jain Tirth, UjjainDani Gate, Ujjain, Madhya Pradesh
In the appBelur Math, West BengalBelur, Howrah district, West Bengal
In the appBrihadeeswara Temple, ThanjavurThanjavur, Thanjavur district, Tamil Nadu
In the appEttumanoor Mahadeva Temple, EttumanoorEttumanoor, Kottayam district, Kerala