Artpark was founded in 1974, one year after Robert Smithson's death, and had an artist's residency program in his honor. The park, created on the site of a former industrial waste dump,[7] became an important site for works of the land art movement.[8] It was the site of Alan Sonfist's Pool of Virgin Earth, a 25-foot-diameter (7.6 m) clay basin for catching aerial seeds, and projects by several women artists in the 1970s, including Michelle Stuart, Alice Adams and Agnes Denes and Nancy Holt.[9] It continued to be an important laboratory for outdoor sculpture,[10][11] with over 200 artists and collectives creating art and installations at the site between 1974 and 1984.[12]