Metro Detroit has an extensive toll-free network of freeways administered by the Michigan Department of Transportation. Four major Interstate Highways surround the city. Detroit is connected via Interstate 75 (I-75) and I-96 to Kings Highway 401 and to major Southern Ontario cities such as London, Ontario and the Greater Toronto Area. I-75 (Chrysler and Fisher freeways) is the region's main north–south route, serving Flint, Pontiac, Troy, and Detroit, before continuing south (as the Detroit–Toledo and Seaway Freeways) to serve many of the communities along the shore of Lake Erie.

Which Interstate is the major north-south route?