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.
Pan-American Highway
The Alaska Highway through Alaska, Yukon and British Columbia is commonly considered a de facto northerly extension of the Pan-American Highway, as well as the Dalton Highway in Alaska. In Canada, no particular road has been officially designated as the Pan-American Highway. The National Highway System, which includes but is not limited to the Trans-Canada Highway, is the country's only official interprovincial highway system. However, there are several Canadian routes that are a natural extension of several key American highways that reach the Canada–US border. British Columbia Highway 97 and Highway 2 to Alberta both pick up where the southern end of the Alaska highway leaves off. Highway 97 becomes U.S. Route 97 at the Canada–US border. British Columbia Highway 99 provides an alternate route from Highway 97 just north of Cache Creek that runs through Whistler and Vancouver before ending at the Canada–US border at the north end of Interstate 5 in Washington State, the beginning of the official Pan-American route south of British Columbia. Meanwhile, Alberta Highway 2 runs south and east to Alberta Highway 3 leading into Lethbridge, then south on Alberta Highway 4 to the Canada–US border where it becomes Interstate 15 in Montana, the first official stretch of the Pan-American Highway south of the Alberta route.