The river starts near the southern tip of the Western Ghats(Sahyadri Mountains) at Agastyar Koodam.

[2] The Karamana River originates from the Agasthya Mala in the Western Ghats part of the Thiruvananthapuram district.

It then flows through several hilly eastern towns of Thiruvananthapuram district namely, Meenankal, Cherappally, Utharamcode, Aryanad, Uzhamalackal, Mundela, Perumkulam and Aruvikkara.

Downstream the river enters the Travancore plains and passes towns like Irumpa, Nettayamam, Peyad, Karimankulam, Perukavu, Vilavoorkkal, Choozhattukotta, Pappanamcode, Nemom and Thiruvallam.

Part of the water was diverted into the Kochar channel which in turn fed the Pathrakulam pond (no longer exists) adjacent to current Padmatheerthakulam outside the Padmanabhaswamy Temple.

This was built by Lt Col. Horsley, the author of the earliest English treatise on history of Travancore, and inaugurated in 1853.

[8] Fish species found in the Karamana include Karimeen, Chekkaali, Kariyida, Paruminali, Cherumeen, Vaala, Nedumeen, Aaral, Maalavu and Paaval.

[1] The Karamana has been facing the problems of pollution, acidification and fish kill in recent years.

It is referred to as the ‘Makaraakara’ river in the Jain ascetic Udyodana Suri's 8th century Prakrit text Kuvalayamaala.

Some of the singers, instrumentalists and composers who are associated with the river include Irayimman Thampi, Vadivelu, Neelakanta Sivan and K S Chitra.