The Dumas Brothel was a bordello in Butte, Montana. The brothel was founded by French Canadian brothers Joseph and Arthur Nadeau in 1890 and named after the nominal owner, Delia Nadeau, née Dumas, who was Joseph's wife. It grew considerably through the years, with the miners employed by the city's copper mines often patronizing the establishment. After several changes of the "madams" and continuing pressure from authorities, the brothel closed in 1982, described as "a rare, intact commentary on social history". At the time of its closure, it was the longest operating brothel in the United States, having operated years after prostitution was made illegal. After closing, the brothel changed hands several times, eventually becoming a tourist attraction owned and managed by a series of Butte residents.