This is a bit off-topic, but in researching a book report I'm doing about My Friend Flicka, set in an area between Laramie and Cheyenne, I got some interesting info about the Lincoln Highway: Wikipedia says:
“The Lincoln Highway was the first road across America. This famed transcontinental highway was conceived in 1913 by Carl G. Fisher. The Lincoln Highway spanned more than 3000 miles (5000 km), coast-to-coast, from Times Square in New York City to Lincoln Park in San Francisco, originally through 13 states: New York, New Jersey, Pennsylvania, Ohio, Indiana, Illinois, Iowa, Nebraska, Colorado, Wyoming, Utah, Nevada and California. In 1915, the "Colorado Loop" was removed, and in 1928, a realignment relocated the Lincoln through the northern tip of West Virginia. Thus, there are a total of 14 states through which the highway passed.”
In the present day, the Interstate has about replaced the Lincoln Highway. I'm not sure if in the mid-1980s Ennis and Ellery would have seen the original road; probably not. But it's a part of American history that's been overshadowed by Route 66 for some reason.