List of tallest buildings and structures
The tallest artificial structure is Burj Khalifa, a skyscraper in Dubai that reached in height on January 17, 2009. By April 7, 2008 it had been built higher than the KVLY-TV mast in North Dakota, USA. That September it officially surpassed Poland's Warsaw radio mast, which stood from 1974 to 1991, to become the tallest structure ever built. Guyed lattice towers such as these masts had held the world height record since 1954.
List of tallest buildings in the United States
As of 2018, One World Trade Center in New York City is considered to be the tallest skyscraper in the United States. Its spire brings the structure to a symbolic height of , connoting the year The Declaration of Independence was signed, though the tip of the structure actually is measured at . However, using the more common criterion for the height of a building (the roof, not antenna) the observation deck elevation and highest occupied floor of One World Trade Center are surpassed by Chicago's Willis Tower (formerly and still commonly known as the Sears Tower) and 432 Park Avenue.