Boulder is a suburb of Kalgoorlie in the Western Australian Goldfields, 597 kilometres east of Perth. The Boulder Races were a significant event in early twentieth century goldfields region history. The town maintained its separation from Kalgoorlie until the 1980s, however even prior to that era, many surveys and studies of the towns and their areas tended to join the names. Prior to 1989, Boulder was a town, but it was merged with Kalgoorlie to form the City of Kalgoorlie–Boulder.