One World Trade Center is the primary structure of the reconstructed World Trade Center complex in New York City's Lower Manhattan. One WTC is the highest skyscraper in the U. S., the Western Hemisphere's tallest structure, and the world's sixth tallest building. The supertall tower shares the same title as the old World Trade Center's North Tower, which was demolished in the September 11, 2001, terrorist attacks. On the location of the old 6 World Trade Center, the new tower sits on the northwestern side of the 16-acre World Trade Center complex. The building is bordered on the west by West Street, the north by Vesey Street, the south by Fulton Street, and the east by Washington Street.

David Childs, whose company Skidmore, Owings & Merrill also created the Burj Khalifa and the Willis Tower, is the building's architect. On April 27, 2006, work on underground utility resettlement, footings, and structures for the new structure began. When One World Trade Center topped the Empire State Building in height on April 30, 2012, it became the city's highest tower. On August 30, 2012, the steel construction of the skyscraper was completed. The last element of the skyscraper's tower was placed on May 10, 2013, bringing the building's overall height to 1,776 feet, including the spire. Its height in feet refers to the year the US Declaration of Independence was proclaimed. The One World Observatory was inaugurated on May 29, 2015, and the building was completed on November 3, 2014.

The Port Authority of New York and New Jersey announced on March 26, 2009, that the structure will be formally called 'One World Trade Center,' rather than its vernacular designation of 'Freedom Tower.' The structure comprises 94 stories, with the 104th level being the highest. Five high-rise office buildings will be developed along Greenwich Street as part of the rebuilt World Trade Center complex, and the National September 11 Memorial & Museum, which will be positioned immediately south of One World Trade Center, where the original Twin Towers formerly stood. The new structure is part of a larger effort to commemorate and rebuild after the old World Trade Center complex was destroyed.