Q128: Name the two longest rivers in the United States.

a. Rio Grande and Colorado River
b. Mississippi River and Missouri River
c. Ohio River and Columbia River
d. Hudson River and Mississippi River

Question Background Information

The longest rivers in the United States are the Missouri and Mississippi Rivers, which meet in St. Louis, Missouri and terminate in New Orleans. These two rivers have played a large role in the development of the nation. Without access to them, it’s pretty likely that the U.S. would be far smaller – and another nation (or nations?) might own everything west of the Mississippi.

The length varies based on the year and what exactly is determined to be the source, but the Mississippi runs approximately 2,350 miles long, with the Missouri roughly 100 miles longer. The Mississippi begins at Lake Itasca in Minnesota, whereas the Missouri begins where the Gallatin, Jefferson, and Madison Rivers converge near Three Forks, Montana.

Source: Mississippi River Facts, found at

America gained control over these rivers with the Louisiana Purchase from France in 1803.

President Thomas Jefferson, concerned that the French would cut off access to the Mississippi, thus crippling the United States’ trade, authorized Robert Livingston, the U.S. Minister to France, to negotiate the purchase of New Orleans. After Americans indeed lost access to the New Orleans warehouses, Jefferson sent James Monroe to help Livingston and in 1803, France agreed to sell not only New Orleans but all of Louisiana Territory -- for $15 million, or 3¢ an acre. It was a bargain, for it guaranteed that the United States would have unimpeded access to the Mississippi River... and thus giving its inland states and territories access to the Atlantic Ocean.

Though it may not seem that important today, being able to send and receive goods by water was vital. It was far more economical to load a flatboat or barge in Pittsburgh, PA, or New York, NY, or Marietta, OH, and send it down river to the Mississippi than it was to send the same goods in a horse-drawn wagon. In fact, in some cases, depending on geography, it was close to impossible -- or so expensive that it wasn’t worth the effort. 

Almost everything shipped via the Mississippi passed through New Orleans, which quickly became one of the young nation’s wealthiest cities. The Missouri River, with its abundant populations of beaver and river otter, was a boon to the fur trade, as was the west in general with its buffalo. Fur trappers were able to sell their pelts at the trading posts, which then sent them east via the Missouri and Mississippi. As settlers moved west, they relied on the Mississippi and Missouri, either travelling along them by keelboat or driving their wagon trains alongside. Over time, small towns sprang up next to or near the rivers or their tributaries. These towns were new markets for the businesses back east, allowing them to expand.

Trade and travel along the Mississippi and Missouri Rivers, and some of their tributaries, became easier (and ultimately cheaper) after the invention of the steamboat. These boats were able to travel upstream with far more ease than keelboats, which relied on men literally pushing the boat upstream with long poles. Robert Fulton’s development of the steamboat meant that by the second decade of the 19th century, steamboats were regularly traveling the rivers, creating a vast trading network that would soon connect much of the United States to the Atlantic world. 

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Discussion Prompts

Historically speaking, major cities are usually built on major waterways. The reason is relatively simple: trade. With access to water, buyers and sellers of both raw materials and finished goods could send their products almost anywhere in the world. The ability of major cities to exist without such access is a largely recent event, one aided significantly by the invention of the railroad.

Prompt 1 

While land is important when a nation wants to expand its power, water is equally important. In the case of the United States, access to the two longest rivers mean everything. Name one of the two longest rivers in the United States. What is the name of the other one? Why is access to these waterways important? 

Prompt 2 

The Mississippi and Missouri Rivers helped the United States change from a fledgling nation of 13 states on the Atlantic Coast to one that reached all the way to the Pacific Ocean. How did these two rivers help the nation expand? Are they still as vital to the U.S. as they once were? Why or why not? Use current and past events to support your answer