The Wheeling Suspension Bridge is a suspension bridge spanning the main channel of the Ohio River at Wheeling, West Virginia. It was the largest suspension bridge in the world from 1849 until 1851. Charles Ellet Jr. (who also worked on the Niagara Falls Suspension Bridge) designed it and supervised construction of what became the first bridge to span a major river west of the Appalachian mountains. It linked the eastern and western section of the National Road, and became especially strategically important during the American Civil War. Litigation in the United States Supreme Court concerning its obstruction of the new high steamboat smokestacks eventually cleared the way for other bridges, especially needed by expanding railroads. Because this bridge was designed during the horse-and-buggy era, 2-ton weight limits and vehicle separation requirements now apply.