Robert Smithson's earthwork Spiral Jetty (1970) is located at Rozel Point peninsula on the northeastern shore of Great Salt Lake. Using over six thousand tons of black basalt rocks and earth from the site, Smithson formed a coil 1,500 feet long and 15 feet wide that winds counterclockwise off the shore into the water. In 1999, through the generosity of the artist Nancy Holt, Smithson’s wife, and the Estate of Robert Smithson, the artwork was donated to Dia Art Foundation.