Fort Belle Fontaine
St. Louis County, United States · built 1805
Fort Belle Fontaine, formerly known as Cantonment Belle Fontaine, is a former U.S. military base located in St. Louis County, Missouri, across the Mississippi and Missouri rivers from Alton, Illinois. The fort was the first U.S. military installation west of the Mississippi, in the newly acquired Louisiana Territory, and served as a starting point for many expeditions to the American West.
Fort data from Wikidata (CC0). Summary from Wikipedia (CC BY-SA).