A Brief History of the World's Tallest Buildings

Ostankino Tower
In 1967, Moscow joined the tall-building competition when it unveiled the Ostankino Tower, a 1,772-ft. (540 m) monument to mark the 50th anniversary of the Bolshevik Revolution. It held the tallest title for nine years until Canada finished its CN Tower in 1976. Technically, Chicago's Sears Tower — the 110-story skyscraper built in 1974 and recently renamed the Willis Tower — has more inhabitable floors (visitors can ascend 1,450 ft. [440 m] in Chicago but only 1,180 ft. [360 m] in Moscow) but Ostankino Tower's spire makes it roughly 30 ft. (9 m) higher.

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