Manimala River also known as valla puzha has its origin on the Muthavara Hills in Kottayam district near Peerumedu in Idukki District of Kerala. The river passes through the districts of Kottayam, Pathanamthitta and finally joins the Pamba River at Muttar in Alappuzha District.

Erumeli, Manimala, Mallappally, Kaviyoor, Kalloppara, Thalavadi, Kozhimukku, Mundakayam, Kanjirappally and Champakkulam lies on the banks of Manimala River.  It has a length of 91.73 Km and drainage area of 802.90 Km.Thiruvalla; the name had some relation with the river Manimala which was known as Valla puzha, suggesting that Thiruvalla was at the mouth/bank of river Manimala and hence was known as Valla vai.Valla vai was the ancient name of Thiruvalla is a colloquial form of Sreevallabhapuram, named after the chief deity Sree Vallabha.Kaviyoor  temple is located on the Manimala river bank in Thiruvalla Taluk in Pathanamthitta district. It is an important water way of Central Travancore. Rising in the hills of Kottayam-Idukki ranges, the river flows through the midland plains and joins with Pampa and Manimala junction. The river offers a beautiful view at this spot and flows swiftly striking against the many rocks in the river.

Numerous temples and churches, some of which are well known for their architectural ingenuity, are located on the banks of the river.
Manimala town on one side borders the Ponthanpuzha reserve forest. The famous Holy Magy Forane church, temples at Karikattoor and Kangazha are also famous. Manimala is an enroute destination to Sabarimala.. It is a prominent junction with buses available to Kodungoor, Ponkunnam, Kanjirapally,Karukachal, Kottayam, Changanacherry, Erumely, Ranni etc.
 Erumely; A small river, Koratty originally known as Manimala river, marks the entrance of Erumely town. Erumely is a small town in Kottayam District and Kanjirappally Taluk. It's situated very near to highrange.Myth tells that Lord Sree Ayyappa Swami killed "Mahishi", sister of Mahishasur in this place on the way to collect tiger milk. Mahish means buffalo and "Eruma" in malayalam and hence the name extract "erumakolli". All Hindus who are going for Sabarimala Pilgrimage visit this place. There are two temples in this town of Lord Ayyappa and Famous Petta Thullal is there in November, December & January months. Erumely Nainar Masjid is situated opposite to Erumely Cheriya Ambalam.
Mallappally;River Manimala flows through the heart of Mallappally village and the town situates on the bank of this beautiful river, close to a triple arcaded bridge connecting the town with eastern lands. Kallooppara;Through out the length of Kallooppara Village River Manimala is the eastern border. There are 3 bridge crossings and several ferries to cross manimalayar. Without the river the charm of kallooppara would be different. Kallooppara Bhagavathy Temple is in the bank of Manimalayar. Every year during the summer, the sand beds of manimalayar in kallooppara is the venue for the Orthodox Christian Convention. It is the gateway to the high ranges of Kerala, and is at the border of Kottayam and Idukki districts. It is here that the high ranges of south Kerala start.Mundakayam; is one of the most developed towns in Kerala, with rubber plantations, and greenery. The river Manimala runs through Mundakayam. Nearby locations include Panchalimedu, Kuttikkanam, 15 km drive from Mundakayam town and is around 3500 feet above sea level, Peermade and Thekkady. Kanjirappally;The Christian colonization of Kanjirappally had a profound impact on the history of commerce and agriculture with rubber plantations in these parts.