are there any sports event held here?
Yes, it hosted beach volleyball at the 2012 Summer Olympics, 1st London Polo Championships in 2009 and Sainsburys Anniversary Games 2014.
Horse Guards Parade
Horse Guards Parade hosted beach volleyball at the 2012 Summer Olympics held in London. 
what is "the secret service"? A 1969 British science-fiction television series on which network was it aired? ITV's regional franchises ATV, Granada and Southern who produced it? David Lane was any puppet used in the series? Yes - Father Stanley Unwin is a puppet character in the series who are the voice cast? Stanley Unwin, David Healy, David Graham. where was this series shot? A house in Burnham, Buckinghamshire; Centre Point in London ; and Horse Guards Parade in London what is the purpose of establishment of the last place you mentioned? Horse Guards Parade is the location for the 'headquarters of BISHOP' in the series. what is the use of car park at this location? For much of the late 20th century, Horse Guards Parade was used as a car park for senior civil servants. In March 1997 it was announced that parking was banned.
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Horse Guards Parade [SEP] 2012 Summer Olympics
Horse Guards Parade hosted beach volleyball at the 2012 Summer Olympics held in London. Temporary courts and seating designed by Populous were installed by the Arena Group, much as seating is installed annually for Trooping the Colour. There was one court with a capacity of 15,000 with two tiers and a floodlight tower at each of its four corners, two practice courts to the east of the arena, and a further six practice courts at St. James's Park. Most matches were played on Centre Court, but some matches were played on Court 1 on day 6 of the competition.