Because the River goes through all of the states in America so it's the easiest way to get around from one state to another. I have notes on this so i know that this is the answer
Mississippi river
The Mississippi.
The Mississippi.
the erie canel
The Mississippi River provides water to any number of cities along its route. It also provides water transportation from the Port of New Orleans to points north like St. Louis. The Mississippi also connects to the Ohio River, thus continuing water transportation all the way to Pittsburgh.
Mississippi River
The Hudson River was the main transportation route.
amazon river (fail)
Because of the Gulf of Mexico it has one of the most busiest ports.
the mississippi river
The River Amazon.
The Mississippi Flyway is a bird migration route that generally follows the Mississippi River in the United States and the Mackenzie River in Canada. http://en.wikipedia.org/wiki/Mississippi_Flyway