Moffat Rail Tunnel East Portal, Colorado

The Moffat Tunnel’s east portal is at the base of the old railway route over Rollins Pass, which crosses over the Divide 2,440 feet above the tunnel’s elevation. Work on the Moffat Tunnel started in 1924, and it took four years to drill and blast the 24-foot high, 18-foot wide hole, 6.2 miles though the mountains. It is actively used for freight trains by Union Pacific, and is the fourth longest mainline railway tunnel in the USA.