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
- 149 more...
- ItemStruc001568 - Great Northern Engineering Drawing, Cascade Tunnel, Washington, 1956
- ItemStruc001569 - Great Northern Engineering Drawing, Cascade Tunnel, Washington, 1956
- ItemStruc001570 - Great Northern Engineering Drawing, Cascade Tunnel, Washington, 1956
- ItemStruc001571 - Great Northern Engineering Drawing, Cascade Tunnel, Washington, 1956
- ItemStruc001572 - Great Northern Engineering Drawing, Cascade Tunnel, Washington, 1956
- ItemStruc001573 - Great Northern Engineering Drawing, Cascade Tunnel, Washington, 1956
- ItemStruc001574 - Great Northern Engineering Drawing, Cascade Tunnel, Washington, 1956
- ItemStruc001575 - Great Northern Engineering Drawing, Cascade Tunnel, Washington, 1956
- ItemStruc001576 - Great Northern Engineering Drawing, Cascade Tunnel, Washington, 1956
- 194 more...