History of the world's tallest buildings to be tall, but its true height is not known. For thousands of years, the Great Pyramid in Egypt was the tallest "structure" in the world, but the Great Pyramid is not considered a building since it is not habitable. The earliest structures now known to be the tallest in the world were the Egyptian pyramids, with the Great Pyramid of Giza, at an original height of , being the tallest man-made structure in the world for over 3,800 years, until the construction of Lincoln Cathedral in 1300. From then until the completion of the Washington Monument (capped in 1884)
History of the world's tallest buildings percent, but in the future it is expected to be as low as 46 percent. By 2010, less than half of the 100 tallest buildings in the world were office towers with the majority utilized as residential and mixed use. Presently, only four out of the ten tallest buildings in the world, and twenty eight out of the fifty tallest in the world, are used primarily as offices. A mixed-use tall building contains two or more functions (uses), where each of the functions occupies a significant proportion of the tower's total space. Support areas such as car parks and mechanical