M25 motorway the east of Gravesend and Grays, the Lower Thames Crossing, in order to relieve congestion on the A282 Dartford Crossing and connect the M25 at North Ockendon in Essex with the M2 in Kent. At Junction 5, the clockwise carriageway of the M25 is routed off the main north–south dual carriageway onto the main east–west dual carriageway with the main north–south carriageway becoming the A21. In the opposite direction, to the east of the point where the M25 diverges from the main east–west carriageway, that carriageway become the M26 motorway. The radial distance from London (taken as Charing Cross) varies
London Underground Electronic ticketing in the form of the contactless Oyster card was introduced in 2003. London Underground services on the East London line ceased in 2007 so that it could be extended and converted to London Overground operation, and in December 2009 the Circle line changed from serving a closed loop around the centre of London to a spiral also serving Hammersmith. Since September 2014, passengers have been able to use contactless cards on the Tube. Their use has grown very quickly and now over a million contactless transactions are made on the Underground every day. The Underground serves 270 stations.