It is unlawful to drive an automobile, motorcycle, or other self-propelled vehicle defined in the Vehicle Code within any City park at a speed in excess of 15 miles per hour. (Ord. 2651 § 1, 1995; Ord. 1778 § 1, 1977; Ord. 1179 § 1 Art. 3; prior code § 21.3.2(10)).