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 to reach Brentford and Hounslow. Taken together, this set of routes would be known as the “West London Orbital” railway. In March 2017 the West London Alliance group of local authorities commissioned a study to assess the feasibility of the line so that a decision could be taken as to whether it merited pursuing further. This study found that: In June 2017 Transport for London published the draft Mayor’s Transport Strategy, which stated that London government would work with the relevant boroughs to explore the feasibility of the proposed service, that would become the West London Orbital. In March 2018