The Town of Castle Rock is conveniently located between two major business hubs - 35 miles south of Denver and 40 miles north of Colorado Springs on the I-25 corridor. It is named after a small but prominent butte just north of the town, which is clearly visible from I-25. As of 2005, the city is estimated to have a total population of 35,745 (70,000 in the surrounding area), and is the 19th most populous municipality in the State of Colorado.

Castle Rock is the capital of Douglas County. Douglas County has been nationally recognized as a great place to live, to work and to raise a family. In a May 2004 study by the American City Business Journals (ACBJ), Douglas County ranked fourth in the nation for Quality of Life. The community benefits from its small town charm, beautiful open spaces and close proximity to Denver, Colorado Springs and the Rocky Mountains.

Castle Rock's economy is growing quickly due the area's rate of growth and the affluence of its market.  The workforce is highly educated and skilled and the economic climate welcomes new and expanding businesses. The town was ranked Number 1 in Job Growth by CNN Money Magazine in its 2005 report on the best places to live. The report shows that Castle Rock has seen a 244% increase in jobs since 1990.

Every August the PGA Tour tournament, "The International" is held in Castle Rock at the Castle Pines Golf Club, one of the premier private golf clubs in the country.