London is one of the most congested, and polluted cities in Europe.<br /><br />Londoners were introduced to a congestion charge in 2003, forcing motorists to pay extra when they enter central London. <br /><br />The move had some impact on traffic levels, but in July 2010, authorities introduced a new scheme, in an effort to get more people out of their cars. <br /><br />Al Jazeera's Barnaby Phillips reports from London.
