Argentina. Paraná River Floodplain, Northern Argentina The Paraná River is South America’s second largest, and the river and its tributaries are important transportation routes for landlocked cities in Argentina, Paraguay, Bolivia, and Brazil. This astronaut photograph shows a 29-kilometer (18 mile) stretch of the Paraná, downstream of the small city of Goya, Argentina (just off the top left of the image). Image acquired April 9, 2011.[NASA]