REMOVE

1. rock
2. tunnels
3. exterior views
4. mountains
5. 1945

WHAT

1. Visual Works (hierarchy n … (1)
2. landscapes (representatio … (1)
3. roads (1)

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WHERE

1. Alberta, Canada (1)
2. Pacific Northwest (1)

WHO

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

WHEN

1. 1920 (1)
2. between circa 1929 and ci … (1)