What is the longest road in the United States?

The longest road in the United States is U.S. Route 20 (US 20). Stretching from Boston, Massachusetts, to Newport, Oregon, it covers a distance of approximately 3,365 miles (5,415 kilometers). US 20 travels through a variety of landscapes, including rural areas, forests, mountains, and urban centers, passing through major cities like Chicago and Yellowstone National Park. It is an essential route for cross-country travel and provides a scenic way to explore the diverse geography of the United States.