2007-01-032022-02-032007-01-032022-02-03https://hdl.handle.net/11124/9930Carleton Tunnel on Carleton Highway, Leadville, Colo.Caption title.Date scanned: 2000-10-19.Identifier: SC631.Unmounted; text on front.Held in the Russell L. and Lyn Wood Mining History Archive, Arthur Lakes Library, Colorado School of Mines.Postcard showing the entrance to the Carleton Tunnel with a sign posted with the warning: "Caution: one way passage." The Carleton Tunnel was originally a railroad tunnel known as the Busk-Ivanhoe Tunnel, and it was excavated under the Saguache Range between Leadville and Aspen, a distance of 9,394 feet. The Colorado Midland Railroad began work on the tunnel in 1890, and it was completed in 1893. Twenty men were killed during the construction of the tunnel, but the completion of this line enabled the mines in Aspen to ship their ores to the smelters in Leadville. After World War I, the mining industry in the area began to decline, and the Colorado Midland Railroad went into receivership and closed the Leadville to Aspen line. In 1920, it was converted into an automobile route, and the Busk-Ivanhoe Tunnel was renamed the Carlton Tunnel. However by 1943, the tunnel had become too dangerous to keep open, and it is used now solely for water diversion.Rights management statement available at: http://library.mines.edu/digital/rights.htmlTunnelsStillImage