A30 road
road in southern England

The A30 is a major road in England, running 284 miles (457 km) WSW from London to Land's End.
The road has been a principal axis in Britain from the 17th century to early 19th century, as a major coaching route and post road. It used to provide the fastest route from London to the South West by land until a century before roads were numbered; nowadays much of this function is performed by the M3 (including A316) and A303 roads. The road has kept its principal status in the west from Honiton, Devon to Land's End where it is mainly dual carriageway and retains trunk road status.
Route
London to Honiton
The A30 begins at Henlys Roundabout, where the route stems from the A4 near Hounslow. It crosses the A312 before running south of the Southern Perimeter Road, Heathrow Airport and north of Ashford and Staines-upon-Thames, before reaching the M25 motorway orbital motorway. This first section is entirely dual carriageway. Taken with the A4, its natural continuation which nearby becomes non-dualled towards the M25, the section constitutes one of five routes into the southern half of London which reach Inner London with at least a dual-carriageway, the others being the A3, the M3, the M20 and A2, however approximately one mile before reaching Inner London it is combined with the London variants of the M3 and M4 approaches.
After running astride the M25 to cross the Thames on a bridge designed by Lutyens, the Runnymede Bridge, the A30 runs parallel to but distant from the M3 until southwest of Basingstoke, bypassing Egham and passing through heathland and Sunningdale, Bagshot bypass, and Camberley where the route almost mirrors the Devil's Highway, a stone (stane) street to Calleva Atrebatum (Silchester Roman town), believed to be older still, then passes close to Hook town centre and in the surrounding country the soil is arable.
After the 1930s Basingstoke bypass, the M3 changes direction (between North Waltham and Popham, at the Popham Interchange) the A303 takes over for 2 miles (3.2 km) the A30 losing continuity.
The public source identifies “A30 road” as road in southern England. This brief keeps that definition visible, then builds a research path around road, southern and England.
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Vocabulary and entity names are the principal evidence signals here, because they determine the precision of every later search. The source revision retrieved here is dated May 3, 2026. The linked authority identifier is Q429589. Authority coordinates are 51.475, -0.396. 1 of 1 selected statements include explicit references; 0 carry qualifiers and 0 use preferred rank.
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This entry incorporates text from “A30 road” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.