Sree Nagaraja Temple in Mannarasala is located about three kilometers to the south-east of the bus station in N.H.47 at Haripad, in Alleppey district of Kerala. The temple dedicated to Nagaraja (King of Serpents) is one of the ancient centers of snake worship in Kerala.

The Ayilyam day in Tulam, Kanni and Kumbham months (October- November) in the Malayalam calendar and the Mahasivarathri (Feb- March) are celebrated here with great pomp. The asterism Ayilyam in Kanni is celebrated as the birthday of Nagaraja and that in Kumbham as the birthday of Anantha, the 'Muthassan' of Nilavara (cellar) of the ancestral house here. The most celebrated is the Ayilyam day of Thulam in remembrance of the special visit of the Maharaja of Travancore on this day to the temple. On Ayilyam days, the 'Ezhunnallathu' (royal outing) ceremony is conducted where the idol of 'Nagaraja' is carried by the priests and taken round the temple in a procession and at the end of the Ayilyam Pooja, 'Guruthi', a red liquid made of turmeric and lime, offerings are made. Sivarathri is also celebrated with great fervour here. Poojas are performed on the Saivite model and Deeparadhana (ceremony of lights) in the evening as well as 'Sarpabali', is held only on this day of the year. It is believed that on Sivarathri day, Nagaraja (Serpent God) goes in procession in the direction of the Karoli pond in the temple premises to get a glimpse of the pond, which is believed to be his creation. On the next day of Sivarathri an offering of 'Nurum Palum' held once a year, is performed and left in the cellar of the ancestral house. On the fifth day of Sivarathri, the prasadam of the Nurum Palum is distributed among the members of the family by the Great mother, the priestess who presides over the rituals of the temple.

 'Sarpakalam Pattu' is another ritual conducted once every forty one years in the temple. This ritual involves drawing the figure of the Serpent God on the floor using vegetable colours.