according to Wikipedia..."Centennial was incorporated from portions of unincorporated Arapahoe County in 2001. The city was incorporated to prevent the City of Greenwood Village from annexing certain portions of Arapahoe County to improve its tax base. The money generated from those businesses in the unincorporated portion of Arapahoe County were mostly what funded the majority of the county's services, including road work. There were a number of court cases establishing the right of incorporation to take precedence over the right of annexation. Located entirely within Arapahoe County, and forming part of the Denver-Aurora Metropolitan Area, Centennial was formed February 7, 2001 (the day after its first city officials were elected). The citizens of the formerly unincorporated portion of Arapahoe County had voted to incorporate on September 12, 2000, choosing Centennial as the official name during the vote. It was created on a promise to keep city taxes at 1% (one of the campaigns against incorporation appealed to maintain the unincorporated 3.8% sales tax). Incorporation was approved by 77% of the voters, and the 100,000+ person population of the area made it the largest incorporation in U.S. history as of its creation.

James Michener's 1974 novel Centennial and the subsequent miniseries based on it were set in a fictional town called Centennial, Colorado; however, that town was not based on the actual city of Centennial, Colorado. Neither the geography nor history of Michener's town resemble that of the actual Centennial; Michener's "Centennial" can be placed in Weld County. In addition, the novel predated the formation of the actual city by more than a quarter of a century.

Similarly, Centennial Airport, formerly Arapahoe County Airport, lies adjacent to, but outside of the city limits; it is not named after the city, as it predates it by over 30 years."

Visit the City of Centennial web site at:
www.centennialcolorado.com