The number of rounds fired in a salute depends on the place and occasion. The basic salute is 21 rounds. In Hyde Park and Green Park an extra 20 rounds are added because they are Royal Parks. At the Tower of London 62 rounds are fired on royal anniversaries (the basic 21, plus a further 20 because the Tower is a Royal Palace and Fortress, plus another 21 'for the City of London') and 41 on other occasions. The Tower of London probably holds the record for the most rounds fired in a single salute – 124 are fired whenever the Duke of Edinburgh's birthday (62 rounds) coincides with the Saturday designated as the Queen's official birthday (also 62 rounds).