Built in 1970 of mud, salt crystals, basalt, and dirt, the Spiral Jetty is 1500 feet long and extends far out into the Great Salt Lake.
However no one saw this work for over 30 years. Built during a drought by Robert Smithson, once the water levels returned to normal the spiral was then submerged for three decades, reemerging during a drought in 2004.
The black basalt rocks are now covered with white salt encrustations, and the water has a pink hue to it. The jetty disappears if the lake level is higher than 4,197 feet, and currently the jetty is again in danger of disappearing once again.
There is a plan to restore the jetty, but not everyone agrees with the plan. The sculptor, who died in a plane crash only three years after completing the jetty, expressed a love of entropy and the eroding powers of nature. His project is part of a late 60s sculptural movement known as "Land Art."
It is likely Smithson would have been very happy with the jetty's disappearing act and changing appearance.