Railroad Archives Online
- CollectionD0027 - Timothy Miller Collection
- Series003 - Great Northern Railway Company (U.S.)
- Subseries Level 1009 - Engineering Records
- Subseries Level 2008 - Physical plant drawing
- Subseries Level 3008 - Tunnels
- 3 more...
- ItemStruc000880 - Great Northern Engineering Drawing, Cascade Tunnel, Washington, undated
- ItemStruc000881 - Great Northern Engineering Drawing, Cascade Tunnel, Washington, 1955
- ItemStruc000882 - Great Northern Engineering Drawing, Cascade Tunnel, Washington, undated
- ItemStruc001245 - Great Northern Engineering Drawing, Flathead Tunnel at Twin Meadows, Montana, 1973
- ItemStruc001246 - Great Northern Engineering Drawing, Flathead Tunnel at Twin Meadows, Montana, 1973
- ItemStruc001247 - Great Northern Engineering Drawing, Flathead Tunnel at Twin Meadows, Montana, 1973
- ItemStruc001248 - Great Northern Engineering Drawing, Flathead Tunnel at Twin Meadows, Montana, 1973
- ItemStruc001249 - Great Northern Engineering Drawing, Flathead Tunnel at Twin Meadows, Montana, 1977
- ItemStruc001250 - Great Northern Engineering Drawing, Flathead Tunnel at Twin Meadows, Montana, 1975
- 340 more...