Some modern images of the Alpine Tunnel in Colorado, including restoration work going on there:http://narrowgauge.org/alpine-tunnel/images/The Alpine Tunnel was operated by the Denver, South Park & Pacific and its successors, being abandoned about 1910. Said to be haunted by the ghosts of a train crew asphixiated inside.More info on events, etc..:http://www.narrowgauge.org/alpine-tunnel/html/index.html