
Ernakulam city, the prosperous erstwhile province of Cochin, is growing at a tremendous pace with the hope of becoming the first metropolis of Kerala, is also home to many deities like Poornatrayeesan, Chottanikkara Bhagavathy, Ernakulathappan etc. Ernakulathappan, who dwells in Ernakulam Siva temple, is also called as Rishinagakulathappan in the olden days. The temple faces west towards the vast misty expanses of Kochi lake. Nearby the lakeside, on the eastern side of the road, one could see the temple gateway that opens to a sprawling sandy plain of around two acres. The golden thazhikakudam atop the Sanctum sanctorum is an insignia that speaks volumes of the royalty of the temple. Chuttambalam, not only is structurally vibrant but also is in tune with the temple's architecture.
The sanctum sanctorum of Ernakulathappan is circular, with bronze-tiled roof, possesses an enticing Shiva Linga. The eastern door of the Ernakulathappan's Sree Kovil is always closed eversince a decree of Viwamangalam Swamiyar. Parvathi devi is said to be present there, hence, litting a lamp before the door is believed to invoke divine favour for women who are not lucky enough to get married.
The legend behind the formation of the temple revolves around a boy named Devalan. Devalan was the favourite disciple of Sage Kulu. Once a poisonous snake had bitten Devalan and as a revenge he tied down it. Sage Kulu saw this and cursed Devalan to become a Nagarshi. Without much delay he turned into Nagarshi and wandered about seeking ways to redeem himself from the curse. He came across the Shiva Linga made by Arjuna during his peanance for Pasupathastra(arrow of shiva) and took it with him.

After praying at temples like Ramanatha temple, he arrived at 'Rishinakulam' or
'Rishinagakulam' - the ancient name of present Ernakulam. Finding that the place is suitable for supplication, Nagarshi placed the Shiva Linga on the ground and offered poojas. However, after some period, due to certain harassments, he decided to leave with the Shiva Linga. On attempting to lift the Linga, quite amazingly, Nagarshi found that it had become fixed to the ground and couldn't be moved. It is this Shiva Linga we see as Kirathamoorthi(Shiva appeared before Arjuna in the attire of Kiratha) on the northern side of the temple.
Devalan peformed his rites here and was redeemed from the curse. He was given a seat in heaven along with the other devas. At his request, Shiva and Parvathy appeared here and at the spot, where the divine couple disappeared, surfaced a Shiva linga. It is this 'Gourisankara roopa' that is seen as 'Swayambhulinga' in the main Sanctum Sanctorum. According to some, the consecration customs were done by Lord Parasurama.
Tantric rights are bestowed upon Chennas and Puliyannoor. The sub-deities of the temple are Sastha, Ganapathy and Nagaraja(Serpent-Gods). Once the temple was under the governance of Cheranalloor Karthas and later on taken over by Kochi Kings. The poojas(daily five) were regularised as directed by the famous Vilwamangalam Swamiyar.
The annual festival usually falls during January/February(corresponding to Makaram month) and is spread over 8 days.

The festivity starts with Kodiyettam(hoisting of the temple flag) on the first day evening. On the seventh day there is Pakalpooram, when the deity is being taken out in procession with caparisoned elephants with Panchavadyam and finally terminating at Durbar Hall Ground after the famous Pandimelam and colourful fire works. On the final day around evening, in a solemn ceremony the flag is lowered and the deity is then taken for the Arattu(holy bath) in the nearby temple tank. After that starts the famous Arattu procession with the accompaniment of Panchavadyam. The procession terminates at Durbar Hall Ground. The grand fireworks then bring the curtain down to this weeklong festival.
During all these days Sheeveli is arranged inside the temple and the best available Chendamelam artists are arranged for this. A variety of cultural programmes are also arranged during these days. Special emphasis is given to promote temple arts like Ottanthuallal, Paatakam, Thayambaka, Kathakali, Classical dances, Classical music concerts, Bhajans etc. Annadanam is also arranged. Thousands of people throng the temple for witnessing these programmes. Watching the Pakalpooram and Arattu processions will be an unforgettable experience for anybody. The adjacent Durbar Hall ground becomes a beehive of activities during the festival.
Devotees who dedicate themselves to the Lord of Kochi with utmost devotion are said to be relieved from their sufferings, leading to ultimate salvation.