The City of Louisville is a Home Rule Municipality in Boulder County, Colorado, United States. The city population was 18,376 at the 2010 United States Census. Louisville began as a rough mining community in 1877, suffered through a period of extraordinary labor violence early in the 20th century, and then, when the mines closed in the 1950s, made a transition to a suburban residential community. According to CNN/Money and Money magazine's list of the 100 best places to live in the United States, Louisville was placed third in 2007, first in 2009 and 2011, and second in 2013.