Gayathri River, Gayathripuzha in the vernacular, is a tributary of
Bharathapuzha River. It originates from
Anamalai hills, passes through
Kollengode, Nanmara,
Alathur,
Wadakanchery and
Pazhayannur before joining the Bharathapuzha at Mayannur. Managalam River, Ayalurpuzha, Vandazhipuzha, Meenkara puzhas and Chulliyar are the five main sub-tributaries of this river.