Which city is located at the confluence of the Mississippi and Missouri rivers?

St. Louis is known for its strategic location at the confluence of the Mississippi and Missouri rivers, which has historically made it a significant hub for trade and transportation. The city sits at the point where the Missouri River flows into the Mississippi River, providing access to two major waterways in the United States. This geographic positioning facilitated St. Louis's growth as a vital port city during the westward expansion of the country, making it an important center for commerce, industry, and cultural exchange.

In contrast, New Orleans is further south at the mouth of the Mississippi River, where it empties into the Gulf of Mexico, but does not intersect with the Missouri River. Memphis is located further north along the Mississippi River and is not at the confluence of the Missouri River. Kansas City is situated at the confluence of the Missouri River and the Kansas River, but it is not where the Mississippi and Missouri rivers meet. Thus, St. Louis is the correct answer due to its unique geographical position at the intersection of these two significant rivers.