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 90 in Washington
Interstate 90 (I-90) is a transcontinental Interstate Highway that runs from Seattle, Washington, to Boston, Massachusetts. It crosses Washington state from west to east, traveling from Seattle across the Cascade Mountains and into Eastern Washington, reaching the Idaho state line east of Spokane. I-90 intersects several major north–south highways, including I-5 in Seattle, I-82 and U.S. Route 97 (US 97) near Ellensburg, and US 395 and US 2 in Spokane.