The Gran Chaco is a largely uninhabited, hot and semi-arid lowland natural plains region of the Río de la Plata basin in interior south-central South America. Slightly more than half of this territory lies within Argentina, a third in Paraguay and the remainder in Bolivia.
The Gran Chaco is bounded on the west by the Andes mountain range and on the east by the Paraguay and Paraná Rivers. The Chaco’s northern and southern boundaries are less precise. They are often defined as reaching to the Izozog Swamps in eastern Bolivia at the north and roughly to the Salado River in Argentina to the south. Thus defined, the Gran Chaco extends about 450 miles east to west and about 700 miles north to south, covering approximately 280,000 square miles.
Locals sometimes divide the land by political borders, resulting in the terms "Argentinian Chaco," "Paraguayan Chaco" and "Bolivian Chaco." The name Gran Chaco is of Quechua origin, and means “Hunting Land.”