The Ashtamudi Lake located in the Kollam district of Kerala is the second largest wetland ecosystems in the state. The lake is shaped like a palm with eight prominent arms or channels, which gives it the name `ashtamudi`. The arms of the lake meet at Neendakara near Kollam and evacuates at the Arabian Sea. The river feeds on the Kallada River, which is formed when the Kulathupuzha, the Chedurni and the Kalthuruthy merge together.

The lake is sixteen kilometers in length and is renowned for its scenic beauty. The numerous coconut groves that dot the lakeside enhance the beauty of the lake. The Ashtamudi Lake is regarded as the gateway to Kerala`s famous backwaters, which constitute a group of lakes interconnected by a network of canals. Avicennia officinalis, Bruguiera gymnorrhiza and Sonneratia caseolaris are the flora species that are found near the lake.

Forty-three species of marshy and mangrove associates are also present along with two endangered species Syzygium travencoricum and Calamus rotang. The lake houses fifty-seven species of birds out of which six are migratory and fifty-one species are resident birds. Ninety-seven species of aquatic animals inhabit the lake. It is also the home of palaemonid prawns, edible crabs and black clams. In November 2002, Ashtamudi Lake was marked as a Ramsar site.