Udayanapuram Temple enshrines Lord Subrahmanya and has close connection with Vaikom Mahadeva Temple. Worship at Vaikom is believed to be complete only after worship in the Udayanapuram Temple too and the famous Vaikathu ashtami festival involves a special procession from Udayanapuram at night. Moreover Udayanapuram is considered to have equal sacredness as the renowned Palani Subrahmanya Temple of Tamil Nadu.
The temple has the excellence of architecture in structure and is supported with beautiful legends. Marvellous carvings and mural paintings can be found in the inner walls of Udayanapuram Temple. Located near Vaikom, this Subramanya temple celebrates ‘Thai Pooyam’ festival in the month of Capricon (Nov) and the Ashtami festival in the month of Scorpio. The temple is also famous for its traditional 'Aarattu' after the day of Ashatami. As such the Kartika day and the Shashti falling in the bright lunar fortnight are important days every month attracting a large number of devotees..