Junctions
| M4 Motorway | ||
| Eastbound exits | Junction | Westbound exits |
| No access | J29 | Cardiff East and South A48(M) |
| Cardiff East A4232 | J30 Cardiff Gate services |
Cardiff East A4232 |
| Cardiff North, Merthyr Tydfil A470 | J32 | Cardiff North, Merthyr Tydfil A470 |
| Cardiff West, Cardiff International Airport, Barry, Penarth A4232 | J33 Cardiff West services |
Cardiff West, Cardiff International Airport, Barry, Penarth A4232 |
| Llantrisant, Rhondda, Cardiff Northwest A4119 | J34 | Pendoylan, Cardiff West, to the A48 |
| A48 (M) Motorway | ||
| Eastbound exits | Junction/Interchange | Westbound exits |
| Newport, Chepstow, London M4 |
M4 J29 | Start of A48(M) |
| Start of A48(M) | J29A | No exit |
| A48 (T) | ||
| Eastbound exits | Junction | Westbound exits |
| St Mellons A48 | J29A | Start of A48(T) |
| Bridgend (M4), Pontprennau, Cardiff Gate A4232 |
Pentwyn Interchange | Bridgend (M4), Pontprennau, Cardiff Gate A4232 |
| Pentwyn | Llanrumney Interchange | Pentwyn |
| Cardiff East, Docks, Cardiff Bay A4232 | Llanederyn Interchange | Cardiff East, Docks, Cardiff Bay A4232 |
| Access only | UHW | University Hospital |
| (M4 West), University Hospital, City Centre A470 | Gabalfa Interchange | City Centre, (M4) A470 |
| Start of permanent dual carriageway | Road continues as mostly single carriageway | |
| Llantrisant A4119 | Road junction | City Centre, Llantrisant A4119 |
| Fairwater, St Fagans, Pentrebaine B4488 | Road junction | Fairwater, St Fagans, Pentrebaine B4488 |
| City Centre, Cardiff Bay A4161 | Roundabout | City Centre, Cardiff Bay A4161 |
| St Fagans | Road junction | St Fagans |
| City Centre, Penarth A4232 Barry A4055 (M4), Newport, Bridgend A4232 |
Culverhouse Cross Roundabout |
City Centre, Penarth A4232 Barry A4055 (M4), Newport, Bridgend A4232 |
| Start of A48 (T) | - | End of A48 (T) |
The A48(M) motorway connects Junction 29 to the city centre with exits for the Cardiff suburbs of St. Mellons (westbound only), where it becomes the A48, Pontprennau (M4 junction 30 via the A4232), Pentwyn, Rumney, Llanederyn and also for the University Hospital of Wales.
The A4232 (also known as the Peripheral Distributor Road) connects M4 junction 33 with junction 30 by bypassing through the south of the city. From junction 33, exits are at Culverhouse Cross Interchange, Leckwith Interchange, Ferry Road Interchange (for Barry and Penarth) and Butetown, the road ends at Queen's Gate Roundabout, where the long awaited Eastern Bay Link Road will eventually link with the Southern Way Link Road. It then goes onto the M4 at junction 30 via the A48 (Eastern Avenue) and the Pentwyn Link Road (A4232).
The A470 road is the main North - South Wales route running from Cardiff Bay to Llandudno via exits for the suburbs of Tongwynlais and Taff's Well. The A470 is a major road within the city that provides an important link with the Heads of the Valleys road, Mid and North Wales.
As with many other cities car traffic has caused congestion problems and as such the council has designated bus lanes to improve transport into and out of the city centre. The Welsh Assembly Government is considering the introduction of variable congestion charging in the city centre, but only once there has been significant investment in the city's public transport network.
There are several road and rail bridges that cross the River Taff in Cardiff. These include the Clarence Road Bridge, a comparatively modern bridge which replaced a swing bridge. The original bridge was named after the Duke of Clarence.
Much of Cardiff's central shopping zone is pedestrianised, and further pedestrianisation is planned as part of the current St David's 2 regeneration scheme.
Read more about this topic: Transport In Cardiff