Perhaps the most identifiable symbol of Parliament House is the distinctive flagmast and flag. The Australian flag, which is flown over Parliament House 24 hours a day, seven days a week, marks the exact centre of the building. The flag is about the size of the side of a double-decker bus, measuring 12.8 metres by 6.4 metres. The flagmast is 81 metres high and weighs 220 tonnes, making it one of the largest stainless steel structures in the world.
The flag is changed every four to six weeks. Fourteen flags are rotated regularly so they wear evenly. It takes three people to raise and lower the flag. A hydraulically-operated cage called the Alimak is used to transport two people 60 metres up the flagmast to a platform, while below one person controls the winches used during the operation. The Alimak doesn't remain vertical for the whole journey, but follows the 45 degree angle of the flagpole, which means the occupants spend part of the journey almost lying down. For safety reasons, the flag can't be changed if it is too windy or stormy.