Railroad Archives Online
- FondsD0027 - Timothy Miller Collection
- Cyfres003 - Great Northern Railway Company (U.S.)
- Is-gyfres009 - Engineering Records
- 008 - Physical plant drawing
- 008 - Tunnels
- 155 mwy...
- EitemStruc001574 - Great Northern Engineering Drawing, Cascade Tunnel, Washington, 1956
- EitemStruc001575 - Great Northern Engineering Drawing, Cascade Tunnel, Washington, 1956
- EitemStruc001576 - Great Northern Engineering Drawing, Cascade Tunnel, Washington, 1956
- EitemStruc001577 - Great Northern Engineering Drawing, Cascade Tunnel, Washington, 1956
- EitemStruc001578 - Great Northern Engineering Drawing, Cascade Tunnel, Washington, 1956
- EitemStruc001579 - Great Northern Engineering Drawing, Cascade Tunnel, Washington, 1957
- EitemStruc001580 - Great Northern Engineering Drawing, Cascade Tunnel, Washington, 1957
- EitemStruc001581 - Great Northern Engineering Drawing, Cascade Tunnel, Washington, 1956
- EitemStruc001582 - Great Northern Engineering Drawing, Cascade Tunnel, Washington, 1957
- 188 mwy...