Watch Free Online HD Moviesjoy. The History of American Railroads: The Era of Diesel examines the golden age of America’s passenger railroads, traveling across the United States on legendary trains of the East, South, and West. Featuring routes such as the New York Central, Pennsylvania, B&O, Nashville, Chattanooga & St. Louis, Atlantic Coast Line, Rio Grande, Santa Fe, and Union Pacific, the documentary also explores the difficult transition years of the 1960s and 1970s as America’s great passenger trains made their final journeys.