Milwaukee Eagle Nest Tunnel and Trestle over 16-mile Creek near Francis, MT

(Satellite)

"In the winter of 1980 The Chicago Milwaukee St Paul and Pacific Railroad (Milwaukee Road) abandoned almost two thousand miles of track west of Miles City Montana. The abandonment of the “Pacific Extension” was the largest single railroad abandonment in American history." [1980 Flickr]

Jim Arvites posted

On this Day in History on June 19, 1947

the Milwaukee Road flagship train "Olympian Hiawatha" made its first runs between Chicago and Seattle/Tacoma on a 43 Hour 30 Minute schedule. Picture below of the "Olympian Hiawatha" at Eagle Nest Tunnel in western Montana in 1954.

(Sandy Goodrick Photo)

Glenn Olsen: That would have been the fastest schedule between those cities, beating the Empire Builder's 45 hours.
[A "Little Joe" electric locomotive.]
Lance Erickson: Area privately owned today.
Also American-Rails
"It is somewhat ironic then that 'Lines West' was actually one [of] the railroad's few profitable components when it entered bankruptcy for a final time in 1977."
[But Milwaukee management cooked the books to make it look unprofitable so that they had an excuse to abandon it. The Milwaukee is an example of how bad management can kill a railroad.]

The tunnel is not very long, but the east portal is just a rock cut (i.e. no concrete lining), and it opens out directly onto a trestle.

mtmemory, Montana Historical Society Research Center, Educational Use Permitted
"View of Chicago, Milwaukee, and St. Paul Railway Company train crossing railroad trestle preparing to enter Eagle's Nest Tunnel with Sixteen Mile Creek alongside and mountains and trees in background; passengers and conductor in last railroad car. Note on back: 'The Milwaukee famed 'Olympian' powered by a Baldwin-Westinghouse electric locomotive, is shown at Eagle Nest Tunnel in Montana Canyon (near Ringling) in 1939. The complete absence of smoke and cinders on the railroads electrified districts made it possible for passengers to enjoy the luxury of riding in open observation cars through the grandeur of mountain scenery along the route.'"

Note the blue arrow on this map. It points to the Eagle Nest.

American-Rail

1979 Flickr, the Milwaukee had switched to using diesels.