A312

A312
Name	A312
Country	United Kingdom
Route	312
Length mi	13
Direction a	South
Terminus a	Brentford
Direction b	North
Terminus b	Uxbridge
Counties	Greater London
Maintained by	Transport for London

A312 is a primary road in Greater London linking Brentford in the south with Uxbridge in the north, traversing parts of the London Borough of Hounslow and the London Borough of Hillingdon. The route connects major radial corridors including the A4, M4, A40, and services suburban centres such as Hounslow, Boston Manor, Hayes, and Ruislip Gardens. It forms part of local arterial networks used for commuter, freight and bus services, intersecting with strategic transport nodes like Heathrow Airport and Hillingdon Hospital.

Route description

The A312 begins near Brentford at a junction with the A4 close to Syon Park and proceeds westward through Hounslow town centre, passing landmarks such as Boston Manor House and crossing the Grand Union Canal. It continues northwest as the dual carriageway sections of Great West Road and Hanwell Road before meeting the M4 at junction 3/4 proximity and connecting to Heathrow Airport via adjacent spur links. North of Hayes the road becomes the The Parkway dual carriageway through Hillingdon suburbs, intersecting A40 at Hillingdon Circus and continuing to Uxbridge where it terminates near the junction with the A4020 and the M25 corridor via local connectors. The route passes near transport hubs including Southall railway station, Hayes & Harlington railway station, and Uxbridge tube station on the Piccadilly line and Metropolitan line.

History

Originally formed from pre-motorway era radial roads serving Middlesex market towns, the A312 evolved during the 20th century with significant alterations during the post-war road-building era. Major upgrades in the 1960s and 1970s created dual carriageway sections intended to relieve pressure on the A4 and provide access to expanding Heathrow Airport facilities, linking with schemes associated with the M4 motorway and spurs to London Heathrow Airport Terminal 4. Sections were realigned to accommodate suburban expansion tied to developments by local authorities such as London Borough of Hounslow and planning initiatives by Greater London Council. Later safety and environmental modifications were implemented following reports from Transport for London and reviews prompted by incidents near Hayes and Hounslow Heath.

Junctions and destinations

Key junctions include the southern terminus at Brentford with the A4 and access toward Central London via Chiswick, the interchange with the M4 providing connections to Heathrow Airport and Slough, the Hounslow town centre crossings linking to A315 and A30, the Hillingdon Circus junction with the A40 toward Westminster and Oxford, and the northern terminus approaching Uxbridge with onward routes to Ruislip and Denham. Important local destinations served by these junctions encompass Hounslow High Street, Boston Manor, Hayes Town Centre, Hillingdon Hospital, and recreational sites like Gutteridge Wood and the peripheries of Colne Valley Regional Park.

Public transport and usage

The A312 corridor is a major bus corridor for operators including London Buses routes serving Hounslow, Hayes, and Uxbridge, linking with rail and Underground stations such as Hayes & Harlington railway station (served by Elizabeth line services), Southall railway station (Great Western Main Line), and tube interchanges at Hounslow East and Uxbridge tube station. Peak-time freight movements serve industrial estates near Hayes and Hillingdon, while cycle infrastructure and pedestrian improvements have been added near stations influenced by policies from Transport for London and the Mayor of London's transport strategy. Usage patterns reflect commuter flows toward central London and airport-related traffic to Heathrow Airport.

Future developments and upgrades

Planned interventions focus on junction safety improvements, congestion reduction and active travel enhancements coordinated by Transport for London and the local boroughs of Hounslow and Hillingdon. Proposals have included targeted widening, resurfacing, improved traffic signal coordination linked to Smart motorways technologies on feeder links, upgraded bus priority measures aligning with Mayor of London emissions targets, and cycling schemes connecting to regional routes such as the Grand Union Canal Towpath improvements and extensions toward Colne Valley. Related land-use and regeneration projects around Hayes and Hounslow will influence future traffic demand, in parallel with airport access changes driven by Heathrow Airport Limited planning decisions.

Cultural and notable features

The A312 corridor skirts cultural assets including Boston Manor House, historic parks like Syon Park, and community venues in Hounslow and Uxbridge that host events tied to borough identities. It passes industrial heritage sites around Hayes associated with former works of firms like Marconi Company and post-war commercial growth areas documented in archives of Middlesex County Council and the Greater London Council. Local landmarks visible from the route include the spire of St Lawrence Church, Heston, the campus precincts of Brunel University London nearby, and mural and public art projects commissioned by borough arts partners. The road has featured in local transport studies, community campaigns for safety improvements, and planning debates involving organisations such as Campaign for Better Transport and local civic groups.

Category:Roads in London Category:Transport in the London Borough of Hounslow Category:Transport in the London Borough of Hillingdon