REMOVE

1. railroads
2. trees
3. landscapes (representations)
4. roads
5. 1945
6. 1920

WHAT

1. exterior views (1)
2. forests (plant communitie … (1)
3. mountains (1)
4. railroad stations (1)

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WHERE

1. Lake Louise, Alberta, Can … (1)

WHO

1. Clyfford Still; Still, Cl … (1)
2. Still, Clyfford (1)

WHEN

1. between circa 1929 and ci … (1)