The 2012 Summer Olympic Games, officially the Games of the XXX Olympiad, also known informally as London 2012, began in London, United Kingdom, on 27 July and will continue until 12 August 2012. The first event, the group stages in women's football, began two days earlier on 25 July. Around 10,500 athletes from 204 National Olympic Committees (NOCs) are expected to participate.
Following a bid headed by former Olympic champion Lord Coe and the then Mayor of London Ken Livingstone, London was selected as the host city on 6 July 2005 during the 117th IOC Session in Singapore, defeating bids from Moscow, New York City, Madrid and Paris. London is the first city to officially host the modern Olympic Games three times, having previously done so in 1908 and in 1948.