Petronas Twin Tower

The Petronas Twin Towers (also known as the Petronas Towers or Twin Towers), in Kuala Lumpur, Malaysia were the world's tallest buildings, before being surpassed by the Taipei 101. However, the towers are still the tallest twin buildings and office building in the world.

The Petronas Twin Towers were the tallest buildings in the world until Taipei 101, as measured to the top of their structural components (spires, but not antennas), took over the record. Spires are considered integral parts of the architectural design of buildings, to which changes would substantially change the appearance and design of the building, whereas antennas may be added or removed without such consequences. The Petronas Twin Towers remain the tallest twin buildings in the world.

Designed by Argentine-American architect César Pelli, the Petronas Towers were completed in 1998 and became the tallest buildings in the world on the date of completion. They were built on the site of Kuala Lumpur's race track. Because of the depth of the bedrock, the buildings were built on the world's deepest foundations. The 120-meter foundations were built by Bachy Soletanche, and required massive amounts of concrete.
The 88-floor towers are constructed largely of reinforced concrete, with a steel and glass façade designed to resemble motifs found in Islamic art, a reflection of Malaysia's Muslim religion. Another Islamic influence on the design is that the cross-section of the towers is based on a Rub el Hizb (albeit with circular sectors added to meet office space requirements).


Below the twin towers is Suria KLCC, a shopping mall, and Dewan Filharmonik Petronas, the home of the Malaysian Philharmonic Orchestra.

Petronas, Malaysia's national oil company, set out to build the world's tallest building. Although other buildings such as the Sears Tower have higher occupied floors, a higher antenna, and a higher roof, the Petronas Twin Towers' spires are classified as architectural details and rise to 452 m (1483 feet), giving it the greatest structural height until Taipei 101. Taking advantage of the rules governing building measurements (counting spires but not antennas) has generated controversy over the towers' claim to the title. However, the tradition of including the spire on top of a building and not including the antenna dates back to the rivalry between the Chrysler Building and the 40 Wall Street.

Other buildings have used spires to increase their height but have always been taller overall to the pinnacle when trying to claim the title. In the aftermath of the controversy, the rules governing official titles were partially overhauled, and a number of buildings re-classified structural antenna as architectural details to boost their height rating (even though nothing was actually done to the building).