Railroad Archives Online
- CollectionD0237A - Great Northern Railway Historical Society Cascade Division Collection
- Series003 - Great Northern Railway Company (U.S.)
- Subseries Level 1012 - Cartographic materials
- Subseries Level 2003 - Track profile
- ItemGNRHSCD329 - Great Northern Profile Map 1, Cascade Summit to Skykomish, Washington, 1894
- ItemGNRHSCD330 - Great Northern Profile Map 2, Cascade Summit to Skykomish, Washington, 1894
- ItemGNRHSCD331 - Great Northern Profile Map 3, Cascade Summit to Skykomish, Washington, 1894
- ItemGNRHSCD332 - Great Northern Profile Map 4, Cascade Summit to Skykomish, Washington, 1894
- ItemGNRHSCD333 - Great Northern Profile Map 5, Cascade Summit to Skykomish, Washington, 1894
- ItemGNRHSCD334 - Great Northern Profile Map 6, Cascade Summit to Skykomish, Washington, 1894
- ItemGNRHSCD335 - Great Northern Profile Maps 7 and 9, Cascade Summit to Skykomish, Washington, 1894
- ItemGNRHSCD336 - Great Northern Profile Map 8, Cascade Summit to Skykomish, Washington, 1894
- 6 more...