The Sri Ranganathaswamy Temple or Thiruvarangam is a Hindu temple dedicated to Ranganatha, a reclining form of Hindu deity, Vishnu located in Srirangam, Tiruchirapalli, Tamil Nadu, India . Constructed in the Tamil style of architecture, this temple is glorified in the Thiviya Pirabandham, the early medieval Tamil literature canon of the Alvar saints from the 6th to 9th centuries AD and is counted among the 108 Divya Desams dedicated to Vishnu. The temple follows Thenkalai tradition of worship.
It is one of the most illustrious Vaishnava temples in South India rich in legend and history. Its location, on an island in Cauvery river, has rendered it vulnerable to natural disasters as well as the rampaging of invading armies – Muslim and European – which repeatedly commandeered the site for military encampment. The main entrance, known as the Rajagopuram (the royal temple tower), rises from the base area of around 13 cents (around 5720 sq ft) and goes up to 237 feet (72 m), moving up in eleven progressively smaller tiers. The annual 21-day festival conducted during the Tamil month of Margazhi (December–January) attracts 1 million visitors. Srirangam temple is often listed as the largest functioning Hindu temple in the world, the still larger Angkor Wat being the largest existing temple. The temple occupies an area of 156 acres (631,000 m²) with a perimeter of 4,116m (10,710 feet) making it the largest temple in India and one of the largest religious complexes in the world.
Sriranga Mahathmiyam is the compilation of religious accounts of the temple which detail the origins of its greatness. According to it, Lord Rama, an Avatar of Vishnu, worshiped the idol for a long time, and when he returned victoriously from Lanka after killing Ravana, he gave it to King Vibhishana as a token of appreciation for supporting him against Vibhishana’s own brother, Ravana. When Vibhishana was going via Trichy en route to Sri Lanka, the deity wanted to stay in Srirangam. Ranganatha, captivated by the devotion of a King called Dharma Varma, who was doing penance to have Lord Ranganatha to permanently stay Srirangam, stayed put, promising to cast his benign glance eternally on Lanka. Hence it is that the deity (in a reclining posture) faces South.
As per another account, he was carrying it all the way to his kingdom of Lanka and midway, to rest, he placed the image on the banks of Cauvery. After performing his routine pooja, he tried to lift the Vimana, but it could not be lifted. Mahavishnu appeared to him and said that he desired to stay as Ranganatha in the place, which went on to become Srirangam. Vishnu also desired to watch the Brahmotsavam at Tirucherai. The festivals of the temple are thus considered sacred. It should be noted that the Valmiki Ramayana mentions that Vibhishana received a gift from Sri Rama while returning back to Lanka, but it does not specify the name of the gift. It is the parameshvara Samhita that identifies the gift with the idol of sri Ranganatha.
Silapadikaram (book 11, lines 35–40)
However, archaeological inscriptions are available only from the 10th century AD. The inscriptions in the temple belong to the Chola, Pandya, Hoysala and Vijayanagar dynasties who successively swayed the destinies of the Tiruchirapalli district. They range in date between the 9th and 16th centuries and are registered by the ephigraphical society.
The location where the Ranganathan idol was placed was later covered by an overgrowth of deep forests, due to disuse. After a very long time, a Chola king, chasing a parrot, accidentally found the idol. He then established the Ranganathaswamy temple as one of the largest temple complexes in the world.