Personal vehicles caught and passed rail travel as the primary mode of transportation for Americans in the 20th century. And as cars became more affordable and more people bought them, developing the U.S. rail system became an afterthought to expanding the highway system. Still, the U.S. has a robust rail network, with nearly 140,000 miles of track. While the majority of Americans travel in personal vehicles, approximately 40% of the country's long-distance freight is shipped by train. U.S. railroads ...