Pirihueico Lake is one of Seven Lakes in Panguipullis municipality, southern Chile. The lake is of glacial origin and it is enclosed mountains of the Andes. It is located in a geological fault that includes Panguipulli Lake and Lácar Lake in Argentina. The lake is drained by Fui River. Pirihueico Lake is used as a waterway due to its elonged shape. It is used mostly by vehicles traveling to or from Argentina by the nearby Huahum Pass. For that reason there is a ferry operating between Puerto Fuy and Puerto Pirihueico in the western respectively eastern extreme of the lake.