La Cocha Lagoon is a 39,000-hectare volcanic crater lake located within the Pasto Municipality in Nariño, Colombia.
La Cocha Lagoon is Colombia's second largest inland body of water after Lake Tota in terms of surface area.
Wikipedia https://en.wikipedia.org/wiki/Laguna_de_la_Cocha
Address Colombia
Coordinates 1°5'19.269" N -77°9'4.052" E