REMOVE

1. trees
2. rooftops
3. neighborhoods
4. streets
5. barriers
6. 1967

WHAT

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

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WHERE

1. New York, New York (1)

WHEN

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