From Wikipedia, the free encyclopedia.
The A4 is a major road in England. It runs from London to Avonmouth, near Bristol.
Starting in central London, it runs west via Slough, Maidenhead, Reading, Newbury, Hungerford, Marlborough, Calne, Chippenham, Bath and Bristol.
Also known as the Great West Road, it is closely paralleled by the M4 motorway.
