South Pass is one of the most significant transportation gateways through the Rocky Mountains, valued by Indians, mountain men, Oregon Trail emigrants, Pony Express riders, and miners as a broad, relatively level corridor across the Continental Divide between the Atlantic and Pacific watersheds, bounded by the Wind River Range on the north and the Antelope Hills on the south. Mining has been fundamental to the history of the South Pass region: gold may have been discovered as early as 1842, but gold fever began in 1867 when a sample of South Pass ore reached Salt Lake City, drawing hordes of hopeful fortune seekers to South Pass City, Atlantic City, and Miner's Delight. The boom ended quickly as easily obtained placer gold was exhausted and miners began leaving in the early 1870s, but mining continued. In 1884, Emile Granier began organizing construction of a hydraulic gold mining system that employed many local residents over a ten year period. During the 1930s, the Fisher Dredge Company recovered considerable gold ore from the bed of Rock Creek, and more recently the United States Steel iron ore mine operated near Atlantic City from the early 1960s until 1983. Hard rock mines also reopen periodically and some are presently operating.