Explanation: Sasthamkotta Lake is the largest freshwater lake in Kerala state in the southwest of the country, spring-fed and the source of drinking water for half a million people in the Kollam district. Some 27 freshwater fish species are present.

The water contains no common salts or other minerals and supports no water plants; a larva called “cavaborus” abounds and eliminates bacteria in the water, thus contributing to its exceptional purity. The ancient Sastha temple is an important pilgrimage centre.

Source: https://rsis.ramsar.org/ris/1212