Paraguay is a landlocked country in South America, bordering Brazil, Argentina and Bolivia. The Paraguay River (Spanish: Río Paraguay) divides the country into strikingly different eastern and western regions. Both the eastern region (officially called Eastern Paraguay, Paraguay Oriental, and known as the Paraneña region) and the western region (officially Western Paraguay, Paraguay Occidental, and known as the Chaco) gently slope toward and are drained into the Paraguay River, which separates and unifies the two regions.