 Castle Rock is the 17th most populous municipality in Colorado and is the center of the burgeoning urbanization of the county.Because of its Front Range location between Denver and its inner suburbs and Colorado Springs, many of Castle Rock's residents commute nearly 20 miles to northern Colorado Springs or the Denver Technological Center, better known as "The Denver Tech Center" (DTC), which is an 18-mile drive north on I-25, with Downtown Denver roughly 30 miles north, and Denver International Airport about 45 miles north.In fact, about 80% of Castle Rock residents commute out of town to work.