Lago Vichuquén is a significant coastal lagoon located in the comuna of Vichuquén, within the Provincia de Curicó in Chile's Región del Maule. Situated just 18 meters above sea level, this warm-water lagoon covers an expansive surface area of 40 square kilometers. It forms a key part of the Santuario de la Naturaleza "Laguna Torca," a protected area established in 1975, and is surrounded by a coastal Mediterranean sclerophyllous forest ecosystem. The lagoon is a vital ecological and cultural resource in central Chile. The lagoon is part of a larger coastal system that includes the nearby Laguna de Torca. The primary area for angling is the main body of Lago Vichuquén itself, with its shoreline and nearshore waters. The area near its outflow to the ocean, referenced as the "desembocadura lago Vichuquén," is another distinct zone, likely influenced by tidal exchange and offering different fishing opportunities.