Keezhillam Mahadeva temple is located on the Perumbavoor – Muvattupuzha road at Keezhillam village (6 km from Perumbavoor) in Ernakulam district, Kerala. The 8-day annual festival ends with arattu on the Thiruvathira nakshatra day in Kumbham month.
The annual festival includes all the temple rituals associated with Shiva temples in Kerala. Five caparisoned elephants participate in the annual ezhunnallathu. Traditional temple art forms are part of the festival.
The main deity Shiva worshipped in the temple is known as Perumthrikovilappan. The Shivling in the temple is big in height and breadth. The deity faces east.
There are two pradakshina inside the circular sreekovil. The belief is that the prathishta in the temple was performed by Khara Maharishi.
The Upa Devatas worshipped in the temple are Ganapathy, Ayyappan and Rakshas.