The A2 is a major road in south-east England, connecting London with the English Channel port of Dover in Kent. This route has always been of importance as a connection between London and sea trade routes to Continental Europe. It was originally known as the Dover Road. The M2 motorway has replaced part of the A2 as the strategic route. Unlike the other single digit A-roads in Great Britain, the A2 does not form a zone boundary. The boundary between Zones 1 and 2 is the River Thames. From Wikipedia
