The width of the Amazon River varies from only 1 mile in some places during the dry season to as much as 30 miles in the wet season. The mouth of the Amazon where it meets the Atlantic Ocean is more than 250 miles wide.
The year-round width of the river is as much as 6 miles as far as 100 miles upriver. Large ships can dock all the way up to Iquitos, Peru.
The Amazon River is the second-longest river in the world, after the Nile, at about 4,075 miles. The source of the Amazon is high in the Peruvian Andes, and it has approximately 1,100 tributaries emptying into it.