Boulder is the county seat and most populous city of Boulder County and the 11th most populous city in the U.S. state of Colorado. Located at the base of the foothills of the Rocky Mountains, Boulder is famous for its status as one of the most liberal cities in Colorado, its colorful Western history, being a choice destination for hippies in the late 1960s, and as home of the main campus of the University of Colorado, the state's largest university. Furthermore, the city of Boulder frequently receives high rankings in health, well-being, quality of life, education and art.