The Petronas Twin Towers (Malay: Menara Berkembar Petronas) (also known as the Petronas Towers or just Twin Towers, in Kuala Lumpur, Malaysia were the world's tallest buildings from 1998 to 2004, when their height was surpassed by Taipei 101. The towers remain the tallest twin buildings in the world. The Petronas Twin Towers were the tallest buildings in the world until Taipei 101 was completed in 2004, as measured to the top of their structural components (spires, but not antennas). 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.