The river drains vast tract of fertile plains of Upper Kuttanad in the Alappuzha and Pathanamthitta districts.

[1] The river has its origin in Devar Mala peak of the Western Ghats situated in the Konni Reserve Forest.

Later it flows through the hilly towns of Konni, Kumbazha, Mylapra, Konnithazham, Vettoor, Pathanamthitta, Pramadam, Vallikode and enters into the Upper Kuttanad.

Then the river passes through the towns of Kaipattoor, Nariyapuram, Thumbamon, Venmony, Kulanada, Pandalam, Edappon (Nooranad), Vettiyar, Kollakkadavu and Cheriyanad.

The town derives its name from its association with the river; Pathanamthitta, from the Malayalam words pathanam and thitta, means "houses by the riverside".

The left hand of the idol of Ayyappa at Achankovil Shastha Temple always holds ‘Chandan’ (sandalwood paste) and Thirtha (holy water).

The most important festival here is celebrated from the first to tenth day of Malayalam month Dhanu (December – January).