Sasthamangalathappan Shiva Temple, also known as Sasthamangalam Shiva temple, is located at Poovalamkai near Nileshwar town in Kasaragod district, Kerala. The temple is dedicated to Mahadeva Shiva. The annual Shivratri festival is famous here. The annual temple festival is held on Thiruvathira nakshatra in Kumbha Masam (February – March).
The annual festival is famous for Thidambu nritham and Akhada Panchakshara yajnam. The priest of temple dance carrying the Thidambu of Bhagavan on the day to accompaniment of Melam. Various unique rituals that are performed during Shivratri in neighboring Karnataka state are performed. Various types of abhishekam, homam are part of the festivities.
The temple has as sreekovil with a Shivling. The utsava murti of Bhagavan is taken out during the annual festival and rituals. The Upa Devata worshipped in the temple include Ganapathy.
The pratishta dinam in the temple is held in Kumbha Masam.
Vinayaka Chaturthi in Chinga Masam is of great importance here.