Butte (byōt) [key], city (1990 pop. 33,336), seat of Silver Bow co., SW Mont.; inc. 1879. It is a trade, ranching, and industrial center. Mining dominated the city's life and economy from its establishment in 1862. Copper, as well as zinc, silver, manganese, gold, lead, molybdenum, and arsenic have been extracted from mines in the region; copper is still mined.
First an 1860s gold-hunters' camp, then an 1870s silver center, Butte gained importance when copper was discovered (c.1880) and Marcus Daly with his Anaconda Copper Mining Company began to exploit the "richest hill on earth." A huge open-pit mine, the Berkeley, opened in 1955; its expansion forced the relocation of one fifth of Butte's population.
"The Pit" was abandoned in 1982 and has filled with contaminated water draining from surrounding mines. The city, now the largest Superfund site in the nation, has become, in effect, a laboratory for environmental resuscitation efforts, and a number of pollution-remediation companies are based there. Montana Tech of the Univ. of the Montana is also in the city, and Butte is the headquarters of Deerlodge National Forest. Local attractions include museums of mining and minerals, Our Lady of the Rockies, and the Copper King Mansion, once the home of William A. Clark.