The Amazon River is the largest river in South America and the river with the largest drainage area and flow in the world. It ranks second among the world's rivers, second only to the Nile River, which is 6,695 kilometers long. The Amazon River pours 116,000 cubic meters of water into the Atlantic Ocean every second. Its flow is about three times that of the Sai River, ten times that of the Mississippi River, and sixty times that of the Nile River, accounting for one-fifth of the total flow of rivers into the sea in the world. With abundant water and surging water, the fresh water at the estuary rushes into the Atlantic Ocean for 160 kilometers. Among the tributaries, seven are over 1,600 kilometers long; the longest is the Madeira River, which is over 3,200 kilometers long