Lago Pellegrini is an artificial reservoir nestled in the heart of Argentine Patagonia, situated in the General Roca Department of Río Negro Province, near the city of Cinco Saltos. Resting at an elevation of 270 meters above sea level and covering an impressive 112 km², this substantial body of water was created by filling a naturally depressed area — likely formed through ancient wind erosion — with water diverted from the nearby Neuquén River via a derivation channel. This design serves to regulate river flow in a region where no natural lakes previously existed to perform that function. The lake's relatively shallow average depth of 9.4 meters, combined with a maximum depth of 18 meters and a total volume of over 1 billion cubic meters, creates a diverse aquatic environment that supports both commercial and sport fishing. Its Patagonian setting, open skies, and productive waters make it a notable destination for anglers targeting native and naturalized species.