The Vadakkunathan temple complex covers a vast area, which measures about nine acres. The temple is enclosed by huge stonewalls with entranceways or gopurams in the four key directions. The temple has various peepal trees, which grow on the premises and the huge ground that encircles the shrine. This adds to its overall majestic and beautiful appearance. The great saint Parashurama is believed to have built this temple.
There are three main shrines in the Vadakkunathan temple. These shrines are dedicated to Siva or Vadakkunathan, Shankaranarayana and Rama. The first one is situated on the north side of a circular monument and the image is facing westward. The image of Siva and Parvati are facing east to the back.
There is a double storied shrine for Lord Rama, which is west facing and is located on the southern end. There is another shrine for Shankaranarayana, which is also facing in the west direction and is located between these two sanctums. This shrine houses beautiful murals portraying the story of the Mahabharata and they belong to the 17th century A.D.
There is a small shrine between the Vadakkunathan and the Shankaranarayana sanctums in which the icon of Ganesha can be seen.
Everyday various types of offerings are made to the deities of the Vadakkunathan temple. The abhisheka to Lord Siva is offered traditionally with ghee, which as per the Ayurvedic practice is a cure for several ailments. There is a mahalitiga found here, which is covered with ghee and therefore cannot be seen. It has over the years formed a heap and is about ten feet around the linga.
Oil is offered in the Rama shrine of the Vadakkunathan temple and the one of Shankaranarayana is offered panchagavya. Ganapati is offered sweetened oil cake (appani) and the offering of prasadam and it is very famous here. There are a few small sanctums for other deities (upadevatas) in the circumambulatory passage around the temple.
The khittambalam is located adjacent to the western gopuram. It is one of the most outstanding features of this temple. It is the traditional hall, which was earlier used to stage the 'kuttu', an ancient dramatic form and also for traditional dances. The kuttambalamsin here has special importance because of its huge size and workmanship. It is the most popular among all other kuttambalamsin found here in various temples of Kerala.
Sivarathri is the main festival of this Vadakkunathan temple. But still, the deity is not taken out in procession. The Pooram festival takes place every year in Medam (April-May).