See PETRONAS TOWERS, Malaysia

Petronas Twin Towers, pair of skyscraper office buildings in Kuala Lumpur, Malaysia, that are among the world’s tallest buildings. The Twin Towers, built to house the headquarters of Petronas, the national petroleum company of Malaysia, were designed by the Argentine-born American architect Cesar Pelli; they were completed in 1998. The plan for each tower is identical: an eight-lobed circular structure that contains 88 stories of occupiable space and a pyramid-shaped pinnacle surmounted by a slender steel spire. Both rise to a height of 1,483 feet (451.9 metres), which includes 242 feet (73.6 metres) for pinnacle and spire. Each building is supported by 16 large columns around its perimeter, which, along with the rest of the frame, are made of high-strength, steel-reinforced concrete rather than of structural steel; the exterior sheathing consists of stainless steel and glass. A skybridge two stories tall links the two towers between the 41st and 42nd stories.

In 1996, after the spires had been attached to the buildings (and each had thus reached its full height), the Petronas Twin Towers were declared the world’s tallest buildings, eclipsing the former record holder, the 110-story Sears (now Willis) Tower in Chicago. The roof of the Sears Tower was actually more than 200 feet (60 metres) higher than those of the Twin Towers, but the spires on the towers’ pinnacles were regarded as integral parts of the overall architectural structure (see Researcher’s Note: Heights of buildings). The Twin Towers, in turn, lost their preeminent status in 2003 after a spire was put in place atop the Taipei 101 (Taipei Financial Center) building, in Taipei, Taiwan, and that structure reached a height of 1,667 feet (508 metres).
Source: britannica.com