REMOVE

1. shadows
2. stairs
3. bushes
4. trimming (material)
5. barriers
6. sitting

WHAT

1. Visual Works (hierarchy n … (1)
2. arcades (structural assem … (1)
3. artists (visual artists) (1)
4. benches (furniture) (1)

More 

WHERE

1. New York, New York (1)

WHEN

1. 1964 (1)
2. ca. 1964 (1)