In Kerala ten days onam festival starts with Thripunithura Athachamayam. Thripunithura is a small temple town located in Ernakulam district, Kerala. Tripunithura was the capital of old Cochin state. Athachamayam celebrations also closely linked with Cochin royal family.
Athachamayam is conducted every year on Atham asterism of the Malayalam month Chingam.