Early during my career, I lived in Colorado, and the narrow gauge bug bit hard. I traveled all over chasing the tourist roads, and following the ghosts. My favorite trip was to Alpine Tunnel. Spectacular! The tunnel is 1771.7 feet long; the east portal lies at 11496.5 ft above sea level; the west portal lies at 11521.13 feet above sea level. The first train through occurred 7/19/1882; the last train through occurred 11/10/1910. The track is still intact through the tunnel.