This brochure advertises both Glacier National Park and the Golden Gate Exposition, which was held in both 1939 and 1940. The Great Northern Railway went by Glacier, of course, but no closer to San Francisco than Portland. But railroads never hesitated to solicit business from people going to places that weren’t actually on their rail lines.
Curiously, the cover of this brochure features not a picture of Glacier or the expo but of a steam locomotive, specifically a GN S-2 4-8-4 locomotive. Since GN rival Union Pacific (which did have trains going to the expo as well as to several national parks) already had streamliners in 1940, this seems like a poor choice of photos.
Great Northern used the S-2 locomotives to pull the Empire Builder, often through Glacier Park. The railway also sometimes used its P-2 4-8-2 locomotives as shown in the above photo.