Five feet (15 m) from the bottom of Seattle's Space Needle is the center of gravity for the 605 foot (184 m) tall structure. Constructed in 1962 and serving as an observation tower in Seattle, Washington, it is designed to withstand winds of 200 miles (321.87 km) per hour. The Space Needle’s foundation is 30 feet (9.14 m) deep because it has such a small base in proportion to its height, at an area of just 120 feet (36.58 m). When the concrete was originally poured into the structure’s foundation, it set a record for largest continuous pour of concrete in the US West.
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