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.
Skidmore, Owings &amp; Merrill
One World Trade Center, also known as the Freedom Tower, is located in Manhattan, New York City, and is high, making it the tallest building in the Western Hemisphere. After Daniel Libeskind won the competition for master-planning, SOM was awarded the architectural design contract for the Freedom Tower, despite having withdrawn their entry in the original design competition.