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
West London Orbital – every day, and the London Overground supports this type of travel. London Overground train service improvements are therefore needed to support new jobs and housing throughout inner London and parts of outer London.” The West London Alliance group of local authorities have agreed that the West London Orbital Scheme is to be a shared strategic infrastructure priority across borough boundaries, and that it will be incorporated in to all Local Plans. Discussions are currently underway between West London councils and London government on the future of the scheme. A number of independent analysis of the scheme have been undertaken,