REMOVE

1. rock
2. stairs
3. sky
4. houses
5. barriers
6. audiences

WHAT

1. Visual Works (hierarchy n … (1)
2. artists (visual artists) (1)
3. beards (1)
4. boats (1)
5. buildings (structures) (1)

More 

WHERE

1. Paradise Island, Bahamas (1)

WHEN

1. 1967 (1)
2. 1971 (1)
3. ca. 1969 (1)