The PDR has 3 separate sections; the Capel Llanilltern Interchange (M4 J33) to Queen's Gate roundabout, the Rover Way - Lamby Way roundabout to the Llanedeyrn Interchange (A48) and the Pontprennau Interchange (A48) to the Pentwyn Interchange (M4 J30).
The section from the Capel Llanilltern Interchange on the M4 (junction 33) to the Queen's Gate roundabout is sometimes referred to as the Western Link Road (),[REF] is in length and includes the Capel Llanilltern - Culverhouse Cross Link Road, Ely Link Road, Grangetown Link Road and Butetown Link Road.