Railroads in the United States were built on a far larger scale than those in Europe, both in terms of the distances covered and also in the loading gauge which allowed for heavier locomotives and double-deck trains. The railroad era in the United States began in 1830 when Peter Cooper's locomotive, Tom Thumb, first steamed along 13 miles of Baltimore and Ohio railroad track. In 1833, the nation's second railroad ran 136 miles from Charleston to Hamburg in South Carolina.
Not until the 1850s, though, did railroads offer long distance service at reasonable rates. A journey from Philadelphia to Charleston involved eight different gauges, which meant that passengers and freight had to change trains seven times. Only at places like Bowling Green, Kentucky, the railroads were connected to one another.