Paraná, << `par` uh NAH, >> River is the second longest river in South America, with a length of about 2,485 miles (3,999 kilometers). Only the Amazon River is longer. The Paraná is formed in southern Brazil, where the Rio Grande and Paranaiba River meet. From there, it flows south through Brazil and along the boundary between Brazil and Paraguay. Then it makes a boundary between Paraguay and Argentina, and travels through Argentina. It empties into the Atlantic Ocean through the estuary (funnel-shaped bay) known as the Río de la Plata (Silver River). Ocean vessels can travel through the estuary and up the Paraná as far as Rosario, Argentina, 400 miles (640 kilometers) from the Atlantic. The Paraguay River is the main branch of the Paraná River.
