The Río Pilcomayo is a major river system flowing through the province of Formosa in northern Argentina, forming part of the international border with Paraguay. It is a lowland river characterized by a vast floodplain, creating a complex network of channels, lagoons, and wetlands, particularly within the protected area of the Río Pilcomayo National Park. This unique aquatic ecosystem supports an exceptionally rich fish fauna, making it a premier destination for anglers seeking diverse species in a wild, subtropical environment. The river's slow-moving waters, combined with the protected park status, offer a fishing experience focused on biodiversity and conservation.