On your marks, set, BOJO! Mayor of London Boris Johnson starts 20,000 riders off on 100-mile bike ride from capital to Surrey
Mayor Boris Johnson started the race by waving a Union Jack flag at the Olympic Park in Stratford, east London
Route runs from the Queen Elizabeth Olympic Park, through east, central and south west London to Surrey, then back through central London to finish at The Mall
Up to 20,000 amateurs cyclists are taking part in the event which follows the route of last year's Olympic road race
Around 150 professional cyclists will race a similar route after the amateurs finish this afternoon