The Kerala Backwaters are a chain of brackish lagoons and lakes lying parallel to the Arabian Sea coast (known as the Malabar Coast) of Kerala state in southern India. The network includes five large lakes (including Ashtamudi and Vembanad) linked by 1500 km of canals, both manmade and natural, fed by 38 rivers, and extending virtually the entire length of Kerala state. The backwaters were formed by the action of waves and shore currents creating low barrier islands across the mouths of the many rivers flowing down from the Western Ghats range.
Vembanad is the largest of the lakes, covering an area of 200 sq km, and bordered by Alappuzha, Kottayam, and Ernakulam districts. The port of Kochi (Cochin) is located at the lake's outlet to the Arabian Sea. Ashtamudi Lake is located in Kollam District, and the town of Kollam (Quilon) lies at its outlet.
Connected by artificial canals, the backwaters form an economical means of transit, and a large local trade is carried on by inland navigation. Fishing and fishcuring is an important industry.