Alagar hills have great importance in the Hindu religion; this hill is called Alagar as the Lord Thirumal is known by the name of Alagar here; hence the hills are named after the Lord.

Alagar kovil is a village in Madurai district in the south Indian state of Tamil Nadu. The history and living of the village is centered around Kallazhagar temple. 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 Divyadesams dedicated to Vishnu, who is worshipped as Kallazhagar and his consort Lakshmi as Thirumamagal.

Here ‘Vishnu’ presides as Meenakshi’s brother ‘Azhagar’. During the Chitrai festival in April/May, when the celestial marriage of Meenakshi to Sundareswarar is celebrated, Azhagar travels to Madurai. A gold processional icon called the Sundararajar is carried by devotees in procession from Azhagar Kovil to Madurai for the wedding ritual.  The Alwars have sung in praise of the deity of the place and the hills. In addition, Nakkirar, the Tamil poet has composed several popular poems about this deity. As the place itself suggests, the temple is dedicated to Alagar who is popularly known as Sundararajar. It is said that Alagar kovil attracted pilgrims even in the early days of the Sangam age.

The temple is built on an extensive area in a very picturesque spot, surrounded by the ruins of a historic fort. The impressive main tower at the entrance, believed to have been built by the Pandyan kings, has some beautiful sculptures depicting scenes from the epics. According to historical records, Malayadhwaja Pandyan, son of Kulasekhara Pandyan, who is said to have established the Pandyan kingdom, appears to be the earliest known monarch who patronised this temple. Jatavarman Sundara Pandyan, who reigned during the period 1251-1270 A.D., beautified the ‘vimana’ of the ‘sanctum sanctorum’ with gold plates. Later, during the reign of the Vijayanagar king Krishnadeva Raya, the temple was endowed with revenues from two villages for conducting regular festivals.

Pazhamudhircholai, one of the six abodes of Lord Subramanya is on the same hill, about 4 kms above. Pazhamudhircholai is situated 19 kilometres from the temple town of Madurai. This hill is also known as Vrishabhadri or Idabagiri.

It is said that the Azhagar Kovil was the actual temple for the main deity of the temple, and the deity was later shifted or relocated to Pazhamudircholai during Thirumalai Nayak’s rule in Madurai.

Pazhamudircholai is a fertile hill, blessed with nature’s bounty in the form of innumerable fruits, vegetables and natural springs. It is a dense forest where Valli is supposed to have lived. The temple itself is relatively small with Valli, Deivayanai, and Lord Muruga in a separate shrine. Lord Ganesha is also present in a separate shrine. There is a temple tower and monkeys play around the area. There is another small temple above Pazhamudhir Cholai where local tribes lead their lives.

Among the Arupadaiveedu, Pazhamudircholai is the last. Lord Muruga at Pazhamudircholai is praised in several works of old Tamil literature such as the Silappathikaram, the Ettuthokai and the Pattupattu.

Source:

http://www.alagarkoil.tnhrce.in/

https://en.wikipedia.org/wiki/Alagar_Koyil