Robert Smithson (January 2, 1938 – July 20, 1973) was an American artist known for his use of photography in relation to sculpture and land art. He was a part of the minimalist movement.
Smithson constructed a large jetty into the Great Salt Lake as a work of art, and it is his best known work of art. The varying mineral content and algae of the water produces a gradient of color along the jetty. Smithson documented the construction of the sculpture in a 32-minute color film also titled Spiral Jetty.