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
- 222 more...
- ItemStruc001661 - Great Northern Engineering Drawing, Cascade Tunnel, Washington, 1955
- ItemStruc001662 - Great Northern Engineering Drawing, Cascade Tunnel, Washington, 1956
- ItemStruc001663 - Great Northern Engineering Drawing, Cascade Tunnel, Washington, 1956
- ItemStruc001664 - Great Northern Engineering Drawing, Cascade Tunnel, Washington, 1956
- ItemStruc001665 - Great Northern Engineering Drawing, Cascade Tunnel, Washington, 1955
- ItemStruc001666 - Great Northern Engineering Drawing, Cascade Tunnel, Washington, 1955
- ItemStruc001667 - Great Northern Engineering Drawing, Cascade Tunnel, Washington, 1956
- ItemStruc001668 - Great Northern Engineering Drawing, Cascade Tunnel, Washington, 1956
- ItemStruc001669 - Great Northern Engineering Drawing, Cascade Tunnel, Washington, 1956
- 121 more...