Koelbel Library serves 107,000 residents in the City of Centennial, and it is part of the Arapahoe Library System. The library system maintains 425,000 volumes and circulates 4.5 million items per year. Koelbel Library offers books, movies, online resources, four meeting rooms, three study rooms, a 39-seat theater, public computers, Wi-Fi, copying, printing, faxing, and scanning services.