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
- 74 more...
- ItemStruc001493 - Great Northern Engineering Drawing, Cascade Tunnel, Washington, 1956
- ItemStruc001494 - Great Northern Engineering Drawing, Cascade Tunnel, Washington, undated
- ItemStruc001495 - Great Northern Engineering Drawing, Cascade Tunnel, Washington, 1956
- ItemStruc001496 - Great Northern Engineering Drawing, Cascade Tunnel, Washington, 1956
- ItemStruc001497 - Great Northern Engineering Drawing, Cascade Tunnel, Washington, 1956
- ItemStruc001498 - Great Northern Engineering Drawing, Cascade Tunnel, Washington, 1956
- ItemStruc001499 - Great Northern Engineering Drawing, Cascade Tunnel, Washington, 1956
- ItemStruc001500 - Great Northern Engineering Drawing, Cascade Tunnel, Washington, 1956
- ItemStruc001501 - Great Northern Engineering Drawing, Cascade Tunnel, Washington, 1956
- 269 more...