LEGO architecture 21033, Руководство пользователя, Страница: 4 / 124

Located in the heart of the city, the 110-story Willis Tower was
completed in 1974 at a cost of $175 million. The tower was
the first to use the “bundled-tubular” construction principle,
where nine independent sections were joined together to
provide extra stability against Chicago’s high winds. The
Willis Tower has more than 16,000 bronze-tinted windows
and 28 acres (11.3 ha) of black aluminum cladding or “skin”.
The Ledge, the famous glass balcony that extends from the
tower’s observation deck, leaves visitors standing 1,353 ft.
(412 m) in the air.
Willis Tower
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