<Tr> <Td_colspan="2"> Wimbledon Championships Summer Olympics (2012) </Td> </Tr> <P> Centre Court is the main court at the Wimbledon Championship, the third annual Grand Slam event of the tennis calendar . It is considered the world's most famous tennis court . It incorporates the clubhouse of the All England Lawn Tennis and Croquet Club . Its only regular use for play is during the two weeks a year that the Championships take place . Centre Court has a premier box, known as the Royal Box, for use by the Royal Family and other distinguished guests . </P> <P> A retractable roof was installed in 2009, enabling play to continue during rain and into the night up until a council - imposed curfew of 11 pm . Centre Court, along with No. 1 Court and No. 2 Court, was also host to the tennis competition at the 2012 Summer Olympics . </P> <P> The name "Centre Court" derives from the location of the principal court at the All England Croquet Club's original site off Worple Road, Wimbledon--where the main court was located in the centre of all the other courts . For the first Wimbledon Championship in 1877 a total of 12 courts were available which were laid out in a 3 × 4 grid and there was no actual centre court . This changed in 1881 when the middle two courts of the middle row were combined to form a Centre Court . The name was kept when the club relocated to its present site at Church Road in 1922 . It was not until a further four courts were added in 1980 that Centre Court's location in the grounds again matched its name . </P>

When was the roof put on centre court at wimbledon