The road measures 9.44 miles long and would take a car obeying speed limits 17 minutes to travel its length.
The B4239 is a B Road and is located in the Zone 4 Highways Region.
This is a true long-distance route, journeying through numerous towns like Rumney, CARDIFF, Peterstone Wentlooge, NEWPORT, Duffryn, and St. Brides Wentlooge.
The road connects South Glamorgan and Gwent.