Interstate 55 (I-55) is a major Interstate Highway in the central United States. As with most interstates that end in a five, it is a major cross-country, north-south route, connecting the Gulf Coast to the Great Lakes. The highway travels from LaPlace, Louisiana, at Interstate 10 (I-10) to Chicago, Illinois at U.S. Route 41 (US 41). The major cities that I-55 connects to includes (from south to north) Jackson, Mississippi; Memphis, Tennessee; and St. Louis, Missouri, connecting the states including Louisiana, Mississippi, Tennessee, Arkansas, Missouri, and Illinois.
The section of I-55 between Chicago and St. Louis was built as an alternate route for U.S. Route 66. It crosses the Mississippi River twice: once at Memphis, and again at St. Louis.