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.
U.S. Route 66
Before a nationwide network of numbered highways was adopted by the states, named auto trails were marked by private organizations. The route that would become US 66 was covered by three highways. The Lone Star Route passed through St. Louis on its way from Chicago to Cameron, Louisiana, though US 66 would take a shorter route through Bloomington rather than Peoria. The transcontinental National Old Trails Road led via St. Louis to Los Angeles, but was not followed until New Mexico; instead US 66 used one of the main routes of the Ozark Trails system, which ended at the National Old Trails Road just south of Las Vegas, New Mexico. Again, a shorter route was taken, here following the Postal Highway between Oklahoma City and Amarillo. Finally, the National Old Trails Road became the rest of the route to Los Angeles.