Representatives of the International Olympic Committee were in London today to assess the city's bid to host the Games in 2012.
London is competing against Paris, New York, Madrid and Moscow, which are also being visited; the winning city will be announced in July.
The inspection will last four days and the final report will play a crucial role in the decision.
Paris is considered the favourite, but the London bid leader, Sebastian Coe, has said he believes the gap is narrowing.
