The Kennedy Mine property was named for Andrew Kennedy, who reportedly discovered a quartz ledge in the late 1850s, and the Kennedy Mining Company was formed in 1860 when he and three partners began digging shafts near the present mine property entrance; the mine operated sporadically until closing in 1878, then reopened in 1886 when fifteen investors put up $97,000 as the Kennedy Mine and Milling Co., and with many miles of underground tunnels beneath the area, it extracted $28,600,000 in gold before a government-ordered closure in 1942. The Argonaut Mine, originally known as the Pioneer Mine, was discovered in 1850 by James Hager and William Tudor, underwent serious development after its purchase by the Argonaut Mining Co. in 1893, and operated until 1942, reaching a vertical depth of 5,570 feet through a 63 degree shaft while producing $25,000,000 in gold.