The Wall Street Mill was once owned by a famous local Joshua Tree character Bill Keys who bought it in 1930. The mill was used for "custom milling" meaning that local miners would bring their ore to this mill to be processed.
  The 2-Stamp mill on the site was first built around 1891 and was moved to this site from Pinyon Well in 1933.
 The mill was last operated briefly by Bill Keys in 1966.