The M15 motorway was the designation planned in the late 1960s and early 1970s for use on the

North Circular Road The North Circular Road (officially the A406 and sometimes known as simply the North Circular) is a ring road around Central London in England. It runs from Chiswick in the west to Woolwich in the east via suburban North London, connecting ...

(A406) after it had been upgraded to

motorway A controlled-access highway is a type of highway that has been designed for high-speed vehicular traffic, with all traffic flow—ingress and egress—regulated. Common English terms are freeway, motorway and expressway. Other similar terms i ...

standard. The upgrade was part of the

London Ringways The London Ringways were a series of four 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 con ...

Plan to build motorways throughout London to ease congestion in the central area. Under the Ringways Plan, the North Circular Road was the northern section of Ringway 2. Most of the Ringways Plan was cancelled in 1973 and the upgrade of the A406 took place in a piecemeal fashion during the following three decades. Although much of the road is now grade-separated

dual carriageways A dual carriageway ( BE) or divided highway ( AE) is a class of highway with carriageways for traffic travelling in opposite directions separated by a central reservation (BrE) or median (AmE). Roads with two or more carriageways which are ...

, the improvements have not been carried out to motorway standards and there are still a number of sub-standard sections and many junctions with minor roads. One section of the M15 was constructed in the early 1970s in conjunction with the M11 motorway. The section of A406 between M11 junction 4 and the Redbridge interchange with the A12 was signed as the southern end of the M11 and the Redbridge junction was signed as M11 junction 3. This was a temporary "virtual" designation to avoid driver confusion, because, at the time of opening, although it was legally part of the M15,Pathetic Motorways – M15
/ref> traffic entering this section of road northbound from the Redbridge Roundabout could continue only onto the M11 and traffic heading southbound on the M11 could enter only the section to Redbridge. As the A406 motorway upgrade was not constructed, the designation has never been officially signed and the M15 was abolished when the A406 Redbridge to A13 road was opened.

References

External links

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Simulation of traffic flow around Redbridge Roundabout (RedRag)
{{UK motorways London Ringways Cancelled highway projects in the United Kingdom