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documents the achievements in architecture, engineering, and design in the U.S., including examples as diverse as windmills, one-room schoolhouses, the Golden Gate Bridge, and buildings designed by Frank Lloyd Wright. The site offers searches to thousands of drawings, large-format photographs, and written histories for more than 35,000 historic structures and sites dating from the 17th to the 20th century. (Library of Congress)
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Freestanding spiral staircase |
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