Railroad Archives Online
- ArkivD0027 - Timothy Miller Collection
- Serie003 - Great Northern Railway Company (U.S.)
- Underserie009 - Engineering Records
- 008 - Physical plant drawing
- 008 - Tunnels
- 205 mer...
- ObjektStruc001644 - Great Northern Engineering Drawing, Cascade Tunnel, Washington, 1956
- ObjektStruc001645 - Great Northern Engineering Drawing, Cascade Tunnel, Washington, undated
- ObjektStruc001646 - Great Northern Engineering Drawing, Cascade Tunnel, Washington, 1956
- ObjektStruc001647 - Great Northern Engineering Drawing, Cascade Tunnel, Washington, 1950
- ObjektStruc001648 - Great Northern Engineering Drawing, Cascade Tunnel, Washington, 1956
- ObjektStruc001649 - Great Northern Engineering Drawing, Cascade Tunnel, Washington, 1955
- ObjektStruc001650 - Great Northern Engineering Drawing, Cascade Tunnel, Washington, 1955
- ObjektStruc001651 - Great Northern Engineering Drawing, Cascade Tunnel, Washington, 1955
- ObjektStruc001652 - Great Northern Engineering Drawing, Cascade Tunnel, Washington, 1955
- 138 mer...