🌊 American Bottom

The American Bottom is the flood plain of the Mississippi River in the Metro East region of Southern Illinois, extending from Alton, Illinois, south to the Kaskaskia River. It is also sometimes called the "American Bottoms". The area is about 175 square miles (450 km2), mostly protected from flooding in the 21st century by a levee and drainage canal system. Immediately across the river from St. Louis, Missouri, are industrial and urban areas, but nearby marshland, swamps, and the Horseshoe Lake are reminders of the Bottoms' riparian nature.