Lago Salto Grande is a large reservoir built on the Uruguay River, forming the natural boundary between Argentina and Uruguay. Located approximately 450 kilometers from Buenos Aires near the city of Concordia in Entre Ríos Province, the lake sits at about 35 meters above sea level. The reservoir stretches roughly 144 kilometers in length and approximately 9 kilometers in width, covering a total surface area of 783 km². Its western shore belongs to Entre Ríos Province, Argentina, while the eastern shore falls within Uruguay. The catchment area extends across 224,000 km² spanning both countries. The lake is fed by the Uruguay River and is classified as an artificial reservoir created by the Salto Grande Dam — a significant hydroelectric and engineering landmark that also serves as a popular viewpoint and tourist destination. The surrounding landscape is characterized by agricultural land, pine-eucalyptus plantations, and rice cultivation, with the Uruguay River corridor supporting a rich and diverse aquatic ecosystem. The water carries natural river silt, giving it a characteristic turbidity rather than crystal clarity, typical of large lowland South American reservoirs.