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Last edited 09 Aug 2018
The Space Needle is an observation tower located in Seattle, Washington, built for the 1962 World’s Fair. The tower is a major tourist attraction and in 1999 was registered as an official Seattle landmark.
The artist Edward E. Carlson came up with a concept design for a dominant central structure for the World’s Fair, inspired by the Stuttgart Tower. One of his early sketches resembled a tethered balloon, while another was a balloon-shaped house on a central column anchored by cables. In the end, the futuristic design was a compromise between Carlson and the architect John Graham who turned the balloon design into a flying saucer. Victor Steinbrueck was responsible for introducing the tower’s hourglass profile.
The tower is 184 m (605 ft) high, 42 m (138 ft) wide, and weighs 9,550 tons. It includes the SkyCity revolving restaurant at 150 m (500 ft), and an observation deck at 160 m (520 ft).
An underground foundation was poured 9.1 m (30 ft) deep by 37 m (120 ft) wide. It took 467 concrete trucks one full day to complete what was, at the time, the largest continuous concrete pour attempted in America.
The five-level ‘flying saucer’ deck was balanced so that the restaurant is capable of revolving on a track-and-wheel system that weighs roughly 125 tons and only requires a 1.5 horsepower motor to operate.
In 2000, the Space Needle underwent a $20 million renovation project. This involved a complete redevelopment of the restaurant and top levels, with the addition of exterior lighting and painting. It was also given an extensive clean, for the first time since it was originally completed.
Part of the redevelopment works was to include a spiral staircase leading to the elevator that was part of the original plans but never built. The Legacy Light, or Skybeam, was also unveiled – a powerful beam of light totaling 85 million candela that is shone skyward to mark national holidays and other notable occasions.
The Space Needle has made numerous appearances in films and TV, including ‘Sleepless in Seattle’, ‘The Parallax View’, ‘Frasier’ and ‘Grey’s Anatomy’. It also served as inspiration for the futuristic condominium that was the home of the Jetsens in the cartoon series of the same name.
- Floor-to-ceiling glass has been installed on the interior and exterior of the Observation Deck, opening up the 360° views of the Puget Sound area.
- New exterior glass barriers match the flow of the building, dipping outward slightly and offering a seamless sight line.
- New structural glass barriers replace the wire safety caging on the outer open-air deck.
- A new steel, timber and glass staircase spirals down from the observation deck to the restaurant, arriving at a glass oculus.
- A first-of-its-kind rotating glass floor, 'The Loupe', has been added to the restaurant level, revealing never-before-seen views of the structure below.
In total, the amount of glass has increased by 196%.
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 External references
- Space Needle - Official site
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