M25 motorway Europe's second longest orbital road after the Berliner Ring, which is . Originally built almost wholly as a dual three-lane motorway, much of the motorway has been widened: to dual four lanes for almost half, to a dual five-lanes section between junctions 12 and 14 and a dual six-lane section between junctions 14 and 15. Further widening is in progress of minor sections with plans for managed motorways in many others. To the east of London the two ends of the M25 are joined to complete a loop by the non-motorway A282 Dartford Crossing of the River Thames between Thurrock
Transport in London implement the recommendations. In the 1960s the Greater London Council prepared a drastic plan for a network of London Ringways including the construction of the London Motorway Box which would have involved massive demolition and huge cost to bring motorways into the heart of the city. Resistance from Central Government over the costs and campaigns of objection from local residents caused the cancellation of most of the plans in 1973. By the end of the 20th century policy swung towards a preference for public transport improvements, although the 118-mile (190 km) M25 orbital motorway was constructed between 1973 and 1986