 The road was conceived in the early 1970s and planning began in the late 1970s , by South Glamorgan County Council . The road at that stage was planned to be completed by 1995 and would relieve Ely , Grangetown , Butetown and East Moors of through traffic and as a fast link to the national motorway network via the M4 and A48 ( M ) . The first section of the PDR to be completed was the Southern Way Link Road between Newport Road ( <unk> road ) and the Eastern Avenue ( A48 road ) in 1978 and the last section of the PDR , the Butetown Link Road , was opened to the public in 1995 . 
