Montcortès is the only lake in Pallars Sobirà County of karstic rather than glacial origin and is listed as an area of natural interest. It is fed by an underwater spring, with depths ranging from about 20m to about 40m.
This lake area is a major Pyrenean waterfowl reserve with a wide variety of flora and fauna, some of which are not commonly found in this area.
Hiking trails and horseback routes depart from the lakeside. Bathing and fishing are permitted.
Montcortès Lake is 12km from Gerri de la Sal. Leave the village along the road to Sort, and then turn off to the left towards La Pobleta de Bellveí. Access to the lake is free.