The Amazon River has an estimated 1,100 tributaries, which provide approximately one-sixth of the freshwater that drains into the world's oceans, according to WWF Global. The source of the Amazon River is Carhuastana and begins in the Peruvian Andes mountain range.
Parts of the Amazon are so vast that ships can dock as far inland as Iquitos, Peru. Travel to Iquitos must be done by ship or plane, as there are no roadways. During the wet season, parts of the Amazon are about 31 miles wide, and the waters of the Amazon may be visible at sea before land is visible.