The interstate highway system was started in the 1950s and cut into railroad revenues in the following decade. While the roadbed for trucks was constructed and maintained by the government, the roadbed for trains was built and maintained by the railroads. The U.S. Postal Service switched its business from trains to trucks and airplanes in 1966. Congress combined several troubled railroads into Amtrak in 1971—that pivotal year—to preserve passenger train transport.
