Great Northern Bridge at Priest River, Idaho, September 11, 1990. Other subject classes: Structure, Bridge

Northern Pacific 2502, a U25C, leads two sisters, 2505 and 2506 on eastbound freight number 600 across the viaduct at Sandpoint, Idaho, on April 15, 1965. Photo by J.M. Fredrickson. Other Subject Classes: diesel locomotive, freight train.

Northern Pacific 2502, a U25C, leads two sisters, 2505 and 2506 on eastbound freight number 600 across the viaduct at Sandpoint Idaho, on April 15, 1965. Photo by J.M. Fredrickson. Other Subject Classes: diesel locomotive, freight train.

Northern Pacific 4025, a class Z-3, leads an eastbound extra freight across the high bridge at Dorsey, Idaho, east of Wallace, on May 28, 1952. Photo by J.M. Fredrickson. Other Subject Classes: steam locomotive, freight train, trestle bridge.