|Primary deity||Kallazhagar (Vishnu)|
|Architectural styles||Dravidian architecture|
|History and governance|
Kallazhagar Temple in Alagarkoil, a village in the South Indian state of Tamil Nadu, is dedicated to the Hindu god Vishnu. Constructed in the Dravidian style of architecture, the temple is glorified in the Divya Prabandha, the early medieval Tamil canon of the Azhwar saints from the 6th–9th centuries AD. It is one of the 108 Divyadesam dedicated to Vishnu, who is worshipped as Kallazhagar and his consort Lakshmi as Thirumamagal.
A granite wall surrounds the temple, enclosing all its shrines. The temple has a seven-tiered rajagopuram.
Kallazhagar is believed to have appeared sage Suthapava. The temple follows Thenkalai tradition of worship. Six daily rituals and many yearly festivals are held at the temple, of which the float festival during the Tamil month of Masi (February–March), Navrathri during September–October and Vaikunta Ekadasi during Margazhi (December–January) being the most prominent. The temple is maintained and administered by the Hindu Religious and Endowment Board of the Government of Tamil Nadu.
The legend has it that sage Suthapas (Munivar) was bathing in Nupura Gangai at Azhakar Hill and did not pay heed to Durvasar Maharishi, who was passing by. The enraged Durvasar cursed Suthapas that he would turn into a frog until he is redeemed of his curse by Lord Sundararajar, who is also known as Kallazhakar. The Suthapas Maharishi, who is named as ‘Mandooga maharisi’ munivar because of his frog status, performed ‘thapas’ (prayer) on the banks of river Vaigai, which is otherwise known as Vegavathi, at Thenur. The Lord Kallazhakar comes from his abode in Azhakar Hill to redeem Mandooga Maharishi of his curse, when he is praying. Since days unknown, it is believed that the lord Kallazhakar comes to Thenur via Malaipatti, Alanganallur and Vayalur. In Thenur Mandap, the lord redeems the sage of his curse and leaves for his abode. "During Thirumalai Nayak regime (1623 to 1659 AD), in 1653 the Mandooga Maharishi relieving ritual was shifted to Vandiyur village where the event is performed at Thennur Mandapam, built by Thirumalai Nayak himself,".
Kallazhagar temple covers an area of about 2 acres (0.81 hectares) and has a five-tiered gopuram (gateway tower). The temple in enclosed in a rectangular enclosure with huge granite walls. The central shrine houses the image of the presiding deity, Uragamellayan Perumal in reclining posture on a snake bed similar to that of Srirangam Ranganathaswamy temple. The images of Sridevi and Bhudevi are also housed in the sanctum. There two life size images of Narasimha, the avatar of Vishnu. One of them is shown holding the demon Hiranya and other slaying him. 
The temple houses some rare Vijayanagara sculptures similar to the ones present in Soundararajaperumal Temple, Thadikombu, Krishnapuram Venkatachalapathy temple, Srivilliputhur Divya Desam and Jalakandeswarar Temple, Vellore.
The architecture of the Azhakar temple corresponds to any of those of south Indian temples, with large gopurams and pillared mandapams.The gopuram of the Karuppa swamy shrine depicts the passionate side of human relationship in the form of beautiful statues. Apart from these, it also depicts the evolution of cultural aspects of the local society including a depiction of an Englishman in British police uniforms. There is another half built gopuram on the southern side of the temple which has been used as an artistic backdrop in a few Tamil movie songs.
The Main tower entrance (Mukya Gopuram) always remains closed, with the shrine of Karupana Swami. The very closed door itself is worshipped as Patinettaam padi Karuppan(meaning, the black Lord who (sits) at the Eighteen steps ). There are various legends associated with this. Only Once in a year, the door is opened and Sudarshana Chakra(Or Chakrathaazhvar as the temple devotees mention), the famous Vishnu's wheel, passes over through the open door. Not even the Lord's Utsava Murti(deity for processions and festivals) goes through this passage. This is a centuries-old practice.
The style of the buildings denote, 3rd or early 4th Century construction.
Some research scholars opine that this was earlier a Jain temple, (the somaskanda vimanamfor instance) but which however was later converted into a Vishnu temple. It is true that during archaeological excavations, many Jain caves and inscriptions were found in the same hill around this temple. However, the famous Vaishnava works in Tamil, belonging to the early 4th to 6th Centuries point that to this temple as a Vishnu temple. The famous Silapadikaram too, that belongs to the 3rd Century AD, points out to this temple as a Vishnu temple. During 2013, while cleaning the area on front of Karupana Samy shrine, a big Teppakulam was discovered. Before the whole Teppakulam was covered with sands and bushes.
Kallazhagar temple is revered in Nalayira Divya Prabhandam, the 7th–9th century Vaishnava canon, by Periazhwar and Peyazhwar. The temple is classified as a Divyadesam, one of the 108 Vishnu temples that are mentioned in the book. During the 18th and 19th centuries, the temple finds mention in several works like 108 Tirupathi Anthathi by Divya Kavi Pillai Perumal Aiyangar.
Religious practises and festival
The temple follows the traditions of the Vadakalai sect of Vaishnavite tradition and follows Vaikasana aagama. In modern times, the temple priests perform the pooja (rituals) during festivals and on a daily basis. As at other Vishnu temples of Tamil Nadu, the priests belong to the Vaishnavaite community, a Brahmin sub-caste. Six daily rituals are held at various times of the day and many yearly festivals are held at the temple, of which the float festival during the Tamil month of Masi (February–March), Navrathri during September–October and Vaikunta Ekadasi during Margazhi (December–January) being the most prominent. There are weekly, monthly and fortnightly rituals performed in the temple.
Every year during the Tamil month of Chithirai, Chithirai Thiruvizha is celebrated. Chithirai Thiruvizha is about Meenakshi's (Azhakar's Sister) Marriage and Azhakar itself. First 15 days is about Meenakshi and her marriage and next 15 days is about Azhakar. The main event is Kallazhakar Crossing the Vaigai river. Millions of people gather in vaigai river to see this event. While Kallazhakar enters the river he comes to know that his sister marriage has been ended already, he returns to Karuparayar Mandapam and then he takes ten avatharam then returns to Azhakar Kovil. This temple got a new Car, after 300 years, built with a team of 15 artisans using vengai tree wood for the structure and Burma teakwood for sculptures. The trial run was held on 6 July 2015.
- M. S., Ramesh (1993). 108 Vaishnavite Divya Desams: Divya desams in Pandya Nadu. Tirumalai-Tirupati Devasthanam.
- "Kallazhagar temple". Dinamalar. 2014. Retrieved 31 May 2014.
- Rao, A.V.Shankaranarayana (2012). Temples of Tamil Nadu. Vasan Publications. p. 229–31. ISBN 978-81-8468-112-3.
- S., Gopalakrishnan (December 1996). "The Raṅga-maṇḍapa of the Tāṭikkompu Temple A Study of an Iconographic Programme of the Vijayanagara Tradition". East and West 46 (3/4): 415–431. Retrieved 15 October 2015 – via JSTOR. (subscription required (. ))
- "Alagarkoil gets new car after 300 years". The Hindu. 7 July 2015. Retrieved 6 December 2015.