Giant Olympic rings are towed on The River Thames through Tower Bridge on February 28, 2012 in London, England. With 150 days remaining before the start of the London 2012 games the Olympic rings, measuring 11 metres high by 25 metres wide, are being showcased on the river as Mayor of London Boris Johnson announces details of two new cultural programmes, which will be part of the London 2012 Festival, along with details of other cultural events being organised to celebrate the London 2012 Olympic and Paralympic Games. (Photo by Oli Scarff/Getty Images)