Mangalanatha Swamy temple - Uthirakosamangai:

In the Ramanathapuram district of Tamil Nadu, Uthirakosamangai, also called Mangalanatha Swamy temple, is a Shiva temple that is located close to Ramanathapuram. Three thousand years ago, the temple was in full bloom. The Uthirakosamangai Temple occupies over twenty acres.
Similar to Ramanathapuram, Sethu Madhava Theertham, and Lakshmana Theertham, the temple is revered.The temple is one of the district of Ramanathapuram's most popular tourist destinations.

The most well-known of the temple's many shrines are those of Mangalanathar, Mangalambigai, and Natarajar. One of a kind old maragatha Nataraja idol made of emerald, standing six feet (1.8 metres) tall, is housed in the temple. The temple has six yearly festivals in addition to six daily rituals that take place between 5:30 and 8 p.m. The Tamil Nadu government's Hindu Religious and Endowment Board is in charge of overseeing and maintaining the temple.
According to Hindu mythology, hundreds of rishis, or ascetics, once worshipped Shiva as a kind of penance. Shiva promised the rishis that in recognition of Mandothari, the wife of King Ravana of Sri Lanka, her penance would be acknowledged in the form of a fireball. In Ravana's palace, Shiva manifested as a young child. As Ravana lifted the lovely kid, a little wound sprang from it.

The rishis believed that the fireball that emerged from the Agni Theertham (temple tank) at the same time was caused by Shiva striking Ravana. Out of the thousand, one person stayed to safeguard the vedic literature while the other 999 committed suicide by plunging into the fire. Shiva appeared in the temple as Sahasralingam (thousand lingams) for the 999 and one more for himself after the rishi expressed his satisfaction. It was said that the lone rishi had appeared later in life as Manickavasgar.

This temple is especially well-known for its 11-month-old, Emerald-stone Nataraja idol, which is coated in sandal paste except for January, when it is cleansed and preserved for Darshana. It is also thought that this temple served as the location of Ravana and Mandari's marriage.
In Tamil Nadu, India's Ramanathapuram district sits the Mangalanathaswamy Temple, also called Uthirakosamangai Mangalanathaswamy Temple. It is a Shiva temple. This temple is noteworthy for a number of factors.

Historical Significance: The temple has a 3,000-year history. It is thought to have been built by 1,000 Shiva devotees who simultaneously gained Moksha, or spiritual emancipation, and spans roughly 20 acres of ground.
Deities: There are shrines to Mangalanathar Swami, Mangaleswari Amman, Natarajar, Suyambulingam, Byravar, Datsinamoorthy, Chandikeswarar, and Balabhairav within the complex of the temple. Additionally, there is a holy temple pool.

One of the temple's distinctive features is its five towers, which include seven-tiered royal towers. Visitors can manually move the two majestic yalis, who are legendary beasts like lions, that guard the entryway with stone balls in their teeth.
Religious Significance: The temple is home to the precious five-and-a-half-foot-tall emerald statue of Sage Mangaleswarar. All year long, sandalwood cups hold the cosmic dancing form of Lord Shiva, known as Natarajar. Given that when the temple was founded, the Sun, Moon, and Mars were the only celestial bodies represented, it is thought to be among the world's first Shiva temples.

Historical Legends: The story goes that Ravana's wife, Mandothari, wished to wed the most devout follower of Shiva. A holy book that Lord Shiva gave to the sages to keep guarded. Ravana tried to touch a child who was actually Lord Shiva, but Lord Shiva changed into Agni and everything went crazy. Fearing the fury of Shiva, the sages dove into a hallowed pool that became known as "Agni Theertham." The scripture was saved only by a guru named Manikavasagar. Consequently, the temple honours Manikavasagar with a lingam, which is a symbol of Lord Shiva.

Historical Significance: The Lord taught Goddess Parvati about holy texts, which is where the temple's name, Uttirakosamangai, originates. The temple was a well-known location under the Pandyan monarchs, whose main city was Uttarakosamangai.

Festivals: The temple hosts several important festivals, including Chithirai, Tirukkalyanam, Thervila, and Arudra Darshan.