Spiral Jetty

Spiral Jetty is a work of land art constructed in April 1970 that is considered to be the most important work by American sculptor Robert Smithson. Smithson documented the construction of the sculpture in a 32-minute color film also titled Spiral Jetty. Built on the northeastern shore of the Great Salt Lake near Rozel Point in Utah entirely of mud, salt crystals, and basalt rocks, Spiral Jetty forms a 1,500-foot-long (460 m), 15-foot-wide (4.6 m) counterclockwise coil jutting from the shore of the lake.

In 1999, the artwork was donated to the Dia Art Foundation; it is one of 12 locations and sites owned by the foundation. Since its initial construction, those interested in its fate have dealt with questions of proposed changes in land use in the area surrounding the sculpture. In order to preserve the work, Dia asks that visitors not take existing rocks from the artwork, make fire pits, or trample vegetation. There are no facilities at the site, so visitors must carry any waste away with them.

The sculpture is built of mud, precipitated salt crystals, and basalt rocks. It forms a 1,500-foot-long (460 m), 15-foot-wide (4.6 m) counterclockwise coil originally jutting from the shore of the lake, though due to the drying of the lake, as of 2022 a mile of lakebed separates Spiral Jetty from the shore. Depending upon the water level of the Great Salt Lake, the sculpture is sometimes visible and sometimes submerged.

Smithson reportedly chose the Rozel Point site based on the blood-red color of the water and its connection with the primordial sea. The red hue of the water is due to the presence of salt-tolerant bacteria and algae that thrive in the extreme 27 percent salinity of the lake's north arm, which was isolated from freshwater sources by the building of a causeway by the Southern Pacific Railroad in 1959.

Smithson was reportedly attracted to the Rozel Point site because of the stark anti-pastoral beauty and industrial remnants from nearby Golden Spike National Historic Site, as well as an old pier and a few unused oil rigs. While observing the construction of the piece from a helicopter, Smithson reportedly remarked "et in Utah ego" as a counterpoint to the pastoral Baroque painting et in Arcadia ego by Nicolas Poussin.

To move the rock into the lake, Smithson hired Bob Phillips of nearby Ogden, Utah, who used two dump trucks, a large tractor, and a front end loader to haul the 6,650 tons of rock and earth into the lake. It is reported that Smithson had a difficult time convincing a contractor to accept the unusual proposal. Spiral Jetty was the first of his pieces to require the acquisition of land rights and earthmoving equipment. Phillips often told people that his best-known construction job was "the only thing I ever built that ... was to look at and had no purpose".

Phillips described the use of earth-moving equipment along the lakeside as "tricky", and said of Smithson that "I don't think he had done any geology work or anything on it. He just had in his mind what it should look like.... He just had the eye for it. I assume it was the artist in him." Work began on the jetty in April 1970. The work was constructed twice; the first time requiring six days. After contemplating the result for two days, Smithson called the crew back and had the shape altered to its present configuration, an effort requiring moving 7,000 tons of basalt rock during an additional three days.

Phillips' son appeared on the PBS Antiques Roadshow program in 2017 with a photograph and collection of documents related to the building of the project.