'City' by Michael Heizer
City, a vast ongoing site in central eastern Nevada that Heizer has been working on since 1972, comprises giant earthworks inspired by ancient architectural ruins. City is a piece of earth art located in Garden Valley, a desert valley in rural Lincoln County in the U.S. state of Nevada, near the border with Nye County. The work was begun in 1972 by the artist Michael Heizer and is ongoing.
Covering a space approximately one and a quarter miles long and more than a quarter of a mile wide (2 km by 0.4 km), City is one of the largest sculptures ever created. Using earth, rocks and concrete as building materials and assembled with heavy machinery, the work comprises five phases, each consisting of a number of structures referred to as complexes, with some of the structures reaching a height of eighty feet.