Embalse Potrerillos is a stunning reservoir nestled in the Andes foothills of Mendoza Province, Argentina, formed by the damming of the Río Mendoza on the route toward the Chilean border. The lake stretches approximately 12 kilometers in length and 3 kilometers in width, and its most striking feature is its crystal-clear, turquoise-blue water — a color that shifts brilliantly depending on the angle of the sun. What began as an engineering project to harness the Río Mendoza has evolved into one of the most exciting trout fisheries in the region, drawing fly anglers from across Mendoza Province and the entire country. The reservoir is gaining a well-deserved reputation as a trophy trout destination, with fish sizes that rival those historically associated with Patagonian waters.