A skyscraper is a tall, multistory building with a steel frame and thin walls known as “curtain walls” because they are not load-bearing. Because the steel frame acts as a support skeleton, skyscrapers are often covered in glass or windows, similar in some ways to a Gothic cathedral. While the earliest skyscrapers were built in Midwest cities such as Chicago and St. Louis, some of the most famous early skyscrapers are New York’s Chrysler Building (1930) and Empire State Building (1931). Along with the development of skyscrapers came the need to introduce new fire-proofing and elevator technology.