This graph shows how tonnage was carried by the different forms of freight transportation in the United States in the second half of the 20th century.

Railroads experienced a low point in freight traffic around 1960 — less than 600 billion ton-miles.

Up to that time, the record for rail cargo carried was 746 billion ton-miles, set in 1944 at the height of World War II. In that year, 69 percent of all intercity freight ton-miles were by rail.

Railroads did a massive job during that war, carrying nearly all military cargo from factories to both east- and west-coast ports, and handling the bulk of intercity domestic freight at the same time. Almost all soldiers and sailors reached their ports of embarcation by train. Railroads in 1944 handled 76 percent of all intercity passenger-miles carried by commercial carriers (rail, bus, air, waterways). But in that year, automobiles were already surpassing railroads in intercity travel — by almost twice as much.

Railroad freight rebounded after 1960. Rail freight surpassed World War II's peak in 1970, when 771 billion ton-miles went by rail.

After partial de-regulation (the Staggers Act of 1980), annual rail freight exceeded one trillion ton-miles in 1990. Railroads' portion each year of intercity commercial freight — compared to highway, waterway, pipeline, and air — never fell below 37 percent. In 2000, it was 41 percent.

(Sources: Eno Foundation and U.S. Department of Transportation)

This is an image of modern railroading at the end of the 20th century. Two freshly painted diesel locomotive "units" pull a train carrying freight "containers" from the Port of Los Angeles, heading eastbound.

Trains like this often go on coast-to-coast runs and can arrive at a container terminal on the opposite coast in as little as four days. Other container-loaded trains go to domestic destinations.

A common use of containers — called intermodal containers because they are transported equally well by ship, truck, and rail — is in "land bridge" operations, which began in the 1980s. Products of east Asia go via the Pacific Ocean to a west-coast container terminal in the U.S. or Canada, then go by rail to an east-coast port, and then travel by sea to Europe. Such a routing is often faster than going through the Panama Canal.

Trains with other types of freight cars carry (in approximate order of importance by volume) coal, industrial chemicals, new motor vehicles, grain, other farm products, minerals, lumber, paper, heavy machinery, and many other commodities, including scrap steel and paper for recycling.