The city was named for the leads or lodes of the deposits of valuable ores.  It is the site of the Homestake Mine, the largest, deepest (8,240 feet [2,510 m]) and most productive gold mine in the Western Hemisphere before closing in January 2002. By 1910, Lead had a population of 8,382, making it the second largest town in South Dakota. Lead was founded as a company town by the Homestake Mining Company, which ran the nearby Homestake Mine. Phoebe Hearst, wife of George Hearst, one of the principals, was instrumental in making Lead more livable. She established the Hearst Free Public Library in town, and in 1900 the Hearst Free Kindergarten. Phoebe Hearst and Thomas Grier, the Homestake Mine superintendent, worked together to create the Homestake Opera House and Recreation Center for the benefit of miner workers and their families. Phoebe Hearst donated regularly to Lead's churches, and provided college scholarships to the children of mine and mill workers. In the early 1930s, due to fear of cave-ins of the miles of tunnels under Lead's Homestake Mine, many of the town's buildings located in the bottom of a canyon were moved further uphill to safer locations. Lead and the Homestake Mine have been selected as the site of the Deep Underground Science and Engineering Laboratory, a proposed NSF facility for low-background experiments on neutrinos, dark matter, and other nuclear physics topics, as well as biology and mine engineering studies. In 1974, most of Lead was added to the National Register of Historic Places under the name of the "Lead Historic District". Over four hundred buildings and 580 acres (230 ha) were included in the historic district, which has boundaries roughly equivalent to the city limits.