Delaware Route 9A (DE 9A) is a two- to four-lane road in Wilmington, Delaware that serves as the primary access route to the Port of Wilmington as well as provide access to Interstate 495 (I-495). The official designation of the route runs along Terminal Avenue between DE 9 and the Port of Wilmington, interchanging with I-495. Signage has the route continuing north along Christiana Avenue to an intersection with U.S. Route 13 (US 13) and DE 9 for a total length of . Christiana Avenue originally became a state highway in the 1920s, serving as part of US 40 that connected to a ferry across the Delaware River to Penns Grove, New Jersey. US 40 was removed from this road in the 1930s and it later became part of DE 48, which was subsequently removed in the 1950s following the discontinuance of the ferry. DE 9A was designated by 1971. Route description DE 9A begins at an intersection with DE 9 in the city of Wilmington, heading east-southeast as two-lane undivided Terminal Avenue through residential areas. The road widens into a four-lane divided highway and comes to an interchange with I-495. Past I-495, the road heads through industrial areas, becoming an undivided road as it crosses over Norfolk Southern's New Castle Secondary railroad line at a grade crossing. The road crosses Norfolk Southern's Christiana Avenue Industrial Track before reaching the entrance to the Port of Wilmington at the Christiana Avenue intersection. At this point, DelDOT officially marks the end of DE 9A, but signage shows it turning north onto Christiana Avenue. DE 9A proceeds north-northwest as a two-lane road, passing through more industrial areas and crossing under I-495 again, this time underneath of the I-495 bridge over the Christina River. After this, the route crosses over both the Norfolk Southern's New Castle Secondary and Shellpot Secondary at grade crossings in marshland. The road continues between residential and commercial areas to the west and industrial areas to the east before terminating at both US 13 and DE 9 near the Christina River drawbridge leading into Wilmington's central business district. DE 9A has an annual average daily traffic count of 8,151 vehicles along Terminal Avenue. The portion of DE 9A along Terminal Avenue between I-495 and the entrance to the Port of Wilmington at Christiana Avenue is part of the National Highway System. History What is now DE 9A was a county