Interstate 80
I-80 is the Interstate Highway that most closely approximates the route of the historic Lincoln Highway, the first road across the United States. The highway roughly traces other historically significant travel routes in the Western United States: the Oregon Trail across Wyoming and Nebraska, the California Trail across most of Nevada and California, the first transcontinental airmail route, and except in the Great Salt Lake area, the entire route of the First Transcontinental Railroad. From near Chicago east to near Youngstown, Ohio, I-80 is a toll road, containing the majority of both the Indiana Toll Road and the Ohio Turnpike. I-80 runs concurrently with I-90 from near Portage, Indiana, to Elyria, Ohio. In Pennsylvania, I-80 is known as the Keystone Shortway, a non-tolled freeway that crosses rural north-central portions of the state on the way to New Jersey and New York City.
Interstate 75
I-75 passes through six different states over its routing. The highway runs the length of the Florida peninsula from the Miami area and up the Gulf Coast through Tampa. Further north in Georgia, I-75 connects to Macon and Atlanta before running through Chattanooga and Knoxville and the Cumberland Mountains in Tennessee. I-75 crosses Kentucky, passing through Lexington before crossing the Ohio River into Cincinnati, Ohio. In the Buckeye State, the highway runs up the western side through Dayton before crossing into Michigan north of Toledo. I-75 runs northeasterly along the Lake Erie shoreline and Detroit River into the city of Detroit before turning northwesterly and northward to the Mackinac Bridge where the freeway crosses the strait between Lakes Huron and Michigan. Further north, I-75 approaches the Canadian border down river from Lake Superior, from its origins near the Atlantic Ocean.