United States Government--post Offices, Rock City Freeport, IL 61032 Phone : (815) 865-5714 Business Category Post Offices Government Offices & Public Schools Post Office - Rock City 100 N Main St Rock City, IL 61070 Phone : (815) 865-5714 Business Category Post Offices Toll-Free           (800) ASK-USPS Fax           (815) 865-5346