Kalgoorlie-Boulder, known colloquially as just Kalgoorlie, is a city in the Goldfields-Esperance region of Western Australia, located 595 km (370 mi) east-northeast of Perth at the end of the Great Eastern Highway. The city was founded in 1889 by the amalgamation of the towns of Kalgoorlie and Boulder, which developed in 1893 during the Coolgardie gold rush, on Western Australia's "Golden Mile". It is also the ultimate destination of the Goldfields Water Supply Scheme and the Golden Pipeline Heritage Trail.
At June 2018, Kalgoorlie-Boulder had an estimated urban population of 29,849, a decline from the recent peak of 32,966 in 2013.
The name Kalgoorlie is derived from the Wangai word Karlkurla or Kulgooluh, meaning "place of the silky pears".