Subway Ticket Booth

Chicago's first subway, totalling less than 5 miles in length, was opened in 1943 beneath State Street. The subway was a much-needed necessity although its construction was delayed by physical problems caused by Chicago subsoil: a soft, watery clay that required thick, steel-reinforced concrete to support the subway tubes. Today, Chicago's subway system is joined with the elevated train system, the "El," and stretches throughout the Chicago area.