The worship of serpents is an integral part of the Hindu religious practices and in Kerala, there are several temples dedicated to the serpent Gods. Amongst them, one of the most famous and considered to be most powerful is the Mannarasala Sree Nagaraja Temple which is situated at Mannarasala in the district of Alappuzha. The Mannarasala Sree Nagaraja Temple is also believed to be the only major temple in Kerala that has a female priest. This priestess is also known as the Mannarasala Amma. 

It is widely believed that the legend of the Mannarasala Sree Nagaraja Temple lies interspersed with the ancient story of the origin of the land of Kerala in itself. 

As the tale goes, when Lord Parasurama cleaved out the land that is today known as Kerala, the land was infertile and infested with snakes. Therefore, he sought out the blessings and support of the Snake God, Nagaraja. The Serpent King agreed to relocate to a place that is today known as Mannarasala. It is here that Lord Parasurama consecrated an idol of the Serpent King and assigned a Brahmin to conduct daily rituals for Nagaraja. 

One day a forest fire killed hundreds of snakes and the injured ones were forced to seek shelter in the pits that surrounded the area where the temple stands today. It is said that the wife of the Brahmin helped the injured serpents by anointing them with tender coconut water, milk and turmeric. That night Nagaraja is believed to have appeared in her dreams and as he was pleased with her selfless behaviour he promised to be reborn as her son. Thus the lady gave birth to a male child and a five hooded serpent child. 

Once the brothers grew up, the five hooded serpent brother vanished into the underground cellar of the ancestral Brahmin home (Illom). He instructed his mother to ensure that she does certain rituals without fail. He insisted that these rituals are to be conducted only by the female members of his mother’s family. To this day the said rituals have been religiously followed. 

Devotees believe that Nagaraja protects the premises even today and throng in large numbers to the temple for the special turmeric powder available here. This powder is believed to have the ability to cure numerous diseases including leprosy. Even women who are not able to conceive children arrive at the temple for the blessings of the deity. Dedicated to the Serpent God Nagaraja, the deity is believed to be endowed with the spirit of Lord Shiva and the form of Hari (Lord Vishnu). The consorts of Nagaraja are Sarpa Yakshi and Naga Yakshi. 

In the Malayalam month of Thulam each year, a festival called the Ayilyam festival is conducted to appease Nagaraja, the Serpent King and other deities here. This falls roughly in the months of September-October. During this time the Brahmin Illom or ancestral home bears witness to special prayers and rituals as well. The procession in which all the serpent idols in the sarpa kaavu or serpent grove and temple are taken to the Illom is one of the most prominent features of the festival. The idol of the presiding deity of the temple, Nagaraja is usually carried by Mannarasala Amma. Noorum Palum, Uruli Kamazhthal etc. are the other major rituals conducted here.