The London 2012 Olympic Games will feature 26 sports, which break down into 39 disciplines. When London hosts the Games of the XXX Olympiad from July 27 - August 12, 2012, it will become the first city to stage the Olympics three times (Athens and Paris have hosted the Summer Games twice, and Lake Placid and St. Moritz have held the Olympic Winter Games twice.)
London also hosted the Games in 1908 and 1948, and both times played a vital role in the development of the modern Olympic movement. London's first go-round, held just 12 years after the first modern Olympics, set a new standard for host cities, particularly with respect to organization. In 1948, London was the site of the Olympics' revival after a 12-year absence because of World War II. Those Games, held in spite of the ruins of the war, were subdued in tone but not in meaning, as the Olympics have been held every four years since.
Sixty-four years later, London will confront a different type of challenge - following the majestic Beijing Games, which re-defined Olympic grandiosity with what was essentially an unlimited budget. London will have no such fiscal luxury, but it does have several other things going for it - principally the ability to integrate historic sites and venues with fresh locales. (Source: NBC)