Upon leaving Delaware City, DE 9 continues west as Wrangle Hill Road, crossing Dragon Creek before passing between PBF Energy's Delaware City Refinery to the north and farm fields to the south. The route turns north onto River Road to head into the oil refinery complex, with DE 72 continuing west on Wrangle Hill Road. Within the oil refinery, the road crosses Norfolk Southern's Reybold Industrial Track railroad line at-grade. DE 9 leaves the industrial area upon crossing marshy Red Lion Creek and continues into a mix of fields, woods, and marshland, with DE 9 Truck heading northwest on Hamburg Road. At this point, the route turns to the northeast and passes between Ommelanden Park to the west and the Ommelanden Hunter Training Center to the east before running between residential subdivisions to the west and the northern training grounds for the Delaware National Guard to the east. DE 9 passes through wooded areas with some homes before continuing into industrial areas and crossing a railroad spur. The road continues into marshland immediately to the northwest of the Delaware River, crossing Army Creek, before entering the city of New Castle.