From hiking on a barrier-free trail, to horseback riding along a creek, Maricopa County Parks offer visitors the best of the Sonoran Desert. At approximately 120,000 acres, Maricopa County is home to the largest regional park system in the United States. All trails within the Maricopa County Park System are for non-motorized use only. Ten parks in the system circle the metropolitan area and all are within a 45-minute drive from downtown Phoenix.