google search warm river id tunnels and it will give you a picture tour of the canyon did some time up there not to long ago
Hemi- Find a UP map. Locate Pocatello. A line ran from there, up to Silver Bow and Butte. North of Pocatello, at Idaho Falls, a branch headed northeast to West Yellowstone. If I recall correctly, wasn't Ashton the end of that line, after it was cut back from West Yellowstone? Boxcab E50
Second is the Poughkeepsie Railroad Bridge in Highland, NY. I have no clue what the tunnel is. Found it, its the Windy Point Tunnel on the old Great Northern in Stevens Pass. Pretty interesting: http://people.msoe.edu/~westr/stevens.htm I'm leaving tommorow and wont be back till tuesday so feel free to move on if you cant get this one.
Well since no one has answered ill tell you the bridge is used by the L & I and the building there beside it is clagg tower which operates the lift bridge