Railroad Archives Online
- ArkivD0027 - Timothy Miller Collection
- Serie003 - Great Northern Railway Company (U.S.)
- Underserie009 - Engineering Records
- 008 - Physical plant drawing
- 008 - Tunnels
- 10 mer...
- ObjektStruc001249 - Great Northern Engineering Drawing, Flathead Tunnel at Twin Meadows, Montana, 1977
- ObjektStruc001250 - Great Northern Engineering Drawing, Flathead Tunnel at Twin Meadows, Montana, 1975
- ObjektStruc001251 - Great Northern Engineering Drawing, Flathead Tunnel at Twin Meadows, Montana, 1973
- ObjektStruc001252 - Great Northern Engineering Drawing, Flathead Tunnel at Twin Meadows, Montana, 1977
- ObjektStruc001433 - Great Northern Engineering Drawing, Cascade Tunnel, Washington, 1956
- ObjektStruc001434 - Great Northern Engineering Drawing, Cascade Tunnel, Washington, 1956
- ObjektStruc001435 - Great Northern Engineering Drawing, Cascade Tunnel, Washington, 1956
- ObjektStruc001436 - Great Northern Engineering Drawing, Cascade Tunnel, Washington, 1956
- ObjektStruc001437 - Great Northern Engineering Drawing, Cascade Tunnel, Washington, 1956
- 333 mer...