The South, thanks to the idea of Confederate General Joe Johnston, was the first to use railroads to transport troops throughout the battlefield, completely overwhelming the North. Although the South contained most of the United States Military Railroad, they only contained around 1/3 of the nation's rails (9,500 miles), creating one of the many weaknesses the South had throughout the war. Not to mention that most of these rails were also only used for Southern passengers, and not completely used to transport troops.