The story of America’s interstates is usually told as a straightforward tale of postwar progress, but the real origins are stranger and more contested than the green signs suggest. The Dwight D.

At first glance, the U.S. Interstate Highway system might seem like a logical grid-based masterpiece with a semblance of order behind its numbering system. Odd-numbered interstates run from north to ...

There are a number of different road designations in the United States, from highways and freeways to interstates and routes, and it can cause some confusion with different laws and regulations.

The Federal-Aid Highway Act of 1956, signed by President Dwight D. Eisenhower on June 29 of that year, funded the Interstate Highway System. Joining this transcontinental system, the Interregional ...