Ringway 4

Ringway 4 was the outermost of the series of four London Ringways, ring roads planned in the 1960s to circle London at various distances from the city centre. They were part of a comprehensive scheme developed by the Greater London Council (GLC) to alleviate traffic congestion on the city's road system by providing high speed motorway-standard roads within the capital linking a series of radial roads taking traffic into and out of the city. Most of the scheme was cancelled in 1973.

Ringway 4 was planned as a new rural motorway/dual carriageway connecting a number of towns around the capital including Sevenoaks, Redhill/Reigate, Leatherhead, Staines, Uxbridge, Watford, St Albans, Hatfield, Hertford and Hoddesdon.

Despite its name, the route of Ringway 4 did not make a complete circuit of London. It was, instead, U-shaped. The planned route started at a junction with the M20 motorway (then also being planned) near Wrotham in Kent and ran west as motorway around the capital to Hunton Bridge near Watford. From Watford the road was to become dual carriageway heading east until it met Ringway 3 near in Essex. The designation for the motorway section was M25.

Construction began on the first section of the motorway between Godstone and Reigate (junctions 6 to 8) in 1973 and included a junction with the M23 motorway which was under construction at the same time.

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