Horse Guards Parade - London

Horse Guards Parade is a large parade ground off Whitehall in central London. It was formerly the site of the Palace of Whitehall's tiltyard, where tournaments were held in the time of Henry VIII. It was also the scene of the annual celebrations of the birthday of Queen Elizabeth I.
The area has been used for a variety of reviews, parades and other ceremonies since the 17th century. It is the site of the annual ceremonies of Trooping the Colour, which commemorates the monarch's official birthday, and Beating Retreat. For much of the late 20th century it was put to a rather less dignified purpose — as a car park for senior civil servants — but this use was ended in the 1990s.
The catalyst for the clearing of the parade ground was the Provisional IRA's mortar attack on 10 Downing Street on 7 February 1991, which was carried out from a vehicle parked near to Horse Guards Parade in Horse Guards Avenue. Vehicles are no longer allowed to park anywhere in the area.