Railroad Archives Online
- CollectionD0011 - James M. Fredrickson Collection
- Series004 - Northern Pacific Railroad Company
- Subseries Level 1014 - Photographs
- Subseries Level 2003 - Railroad Buildings and Structures
- Subseries Level 3007 - Tunnels
- ItemJMF04-02687.0 - Northern Pacific tunnel at Borup, Washington, in 1914.
- ItemJMF04-02688.0 - Northern Pacific mainline at Borup, Washington, circa 1970.
- ItemJMF04-02693.0 - Northern Pacific mainline at Stampede, Washington, circa 1918.
- ItemJMF04-02699.0 - Staff machine, circa 1914.
- ItemJMF04-02700.0 - Northern Pacific Stampede Tunnel at Stampede, Washington, in 1967.
- 20 more...