A4 road (England)

A4
Bath Road
Route information
Length	126.64 mi (203.81 km)
Major junctions
East end	A40 in the City of London
Major intersections	A30 M4 A33 A34 A46 A36 A39 A37 M5
West end	A403 in Avonmouth[1]
Location
Country	United Kingdom
Constituent country	England
Primary destinations	Westminster, Hammersmith, Hounslow, Heathrow Airport, Slough, Maidenhead, Reading, Newbury, Marlborough, Calne, Chippenham, Bath, Bristol
Road network
Roads in the United Kingdom Motorways A and B road zones
← A3 → A5

The A4 is a major road in England from Central London to Avonmouth via Heathrow Airport, Reading, Bath and Bristol. It is historically known as the Bath Road with newer sections including the Great West Road and Portway. The road was once the main route from London to Bath, Bristol and the west of England and formed, after the A40, the second main western artery from London.

Although most traffic is carried by the M4 motorway today, the A4 still acts as the main route from Bristol to London for non-motorway traffic.