A48 road

A48 shield
A48
A48 Eastern Avenue, Cardiff.jpg
The A48 (Eastern Avenue, in Cardiff near the University Hospital of Wales)
Route information
Part of
Maintained by English local authorities and South Wales Trunk Road Agent
Length119 mi (192 km)
Major junctions
From A40
Highnam
Major intersections A466

A449
M4
A4042
A48(M)
A4232
A470
A465
A4138

A483
To A484
Carmarthen
Location
CountryUnited Kingdom
Primary
destinations
Chepstow
Newport
Cardiff
Bridgend
Port Talbot
Neath
Swansea
Carmarthen
Road network
A47 A49

The A48 is a trunk road in Great Britain running from the A40 at Highnam, 3 miles (4.8 km) west of Gloucester, England, to the A40 at Carmarthen, Wales. Before the Severn Bridge opened on 8 September 1966, it was a major route between England and South Wales. For most of its route, it runs almost parallel to the M4 motorway. During times of high winds at the Severn Bridge, the A48 is used as part of the diversion route and is still marked as a Holiday Route.

From Gloucester, the A48 runs through the villages of Minsterworth, Westbury-on-Severn, connects to a link road to Cinderford in the Forest of Dean then through Newnham, Blakeney and since 1995, bypassing Lydney on the west bank of the River Severn. It crosses the England–Wales border at Chepstow and continues westwards close to the South Wales coast passing Newport, Cardiff, Cowbridge, Bridgend, Pyle, Port Talbot, Neath and Swansea, before terminating at the junction with the A40 near the centre of Carmarthen.