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    Not Just For Kids

    Skyscrapers and the WTC Towers

    September 11, 2002 will mark the one-year anniversary of the terrorist attacks on the United States of America and the World Trade Center. “Although the buildings are no more, they will inspire future generations of Americans as the summit of architectural ambition and the zenith of human achievement,” explains Bill Harris, an expert on New York’s historical landmarks. With their rectangular shape looming above the New York skyline, the Twin Towers came to represent an entire city—and even an entire culture.

    Guy F. Tozolli, President of the World Trade Center Association, said: “One of the ways we have addressed the evil of September 11 is by our increased resolve to accomplish our mission of enhancing world trade, global economic development and world peace through supporting the establishment and successful operation of individual World Trade Centers as part of a worldwide alliance of World Trade Centers.” The World Trade Center Association is building a new worldwide headquarters at 60 E. 42nd Street, Suite 1901, New York, N.Y.

    What is a World Trade Center?

    The World Trade Center complex in New York City was not the only World Trade Center, although it was one of the first. Other pioneering World Trade Centers were started in Houston, New Orleans, and Tokyo. New York’s World Trade Center was certainly the most well-known because of its spectacular “Twin Towers.”

    Today, there are nearly 300 World Trade Centers in almost 100 countries. The World Trade Center Association was established in 1970 as a not-for-profit, non-political, multi-national association to facilitate trade by bringing together exporters, importers and service providers.

    Much more than just buildings or organizations, World Trade Centers are symbols of local economic strength and prosperity, as well as bustling hubs of export activity. World Trade Centers bring together private businesses and government agencies involved in global commerce, provide essential trade services, and stimulate the economy of the region that they serve.

    Having a World Trade Center address gives a company prime access and continuous exposure to all of the services, organizations and individuals that are essential for success in international commerce—all under one roof, kind of like a business shopping center.

    Did You Know…?

    A Chicago World Trade Center building was designed in 1982. At 2,500 feet and 210 stories high, it would be even taller than the one in New York, but it was never built.

    Reaching for the Sky

    Skyscrapers were a product of the 18th century Industrial Revolution. New inventions such as steam engines, electricity, steel, and safety elevators changed the way people lived and worked. The first building to be called a skyscraper was the Home Insurance Building, built in Chicago in 1884-1885. Although only ten stories high, it was nevertheless a giant of its time.

    The Great Pyramid in Egypt (480 ft.) was the tallest structure in the world for about 4,500 years, until the Eiffel Tower (986 ft.) was built in France in 1889. After that, skyscrapers kept getting taller and taller. New York City—the skyscraper capitol of the world—seemed to be one huge construction site through the 1920’s as that downtown skyline kept growing upward.

    The Empire State building (1250 ft.) was the tallest building in the world from 1931-1971, and it is once again the tallest building in New York City. The World Trade Towers (1,368 ft.) were the tallest buildings in the world from 1971-1973. Then the Sears Tower in Chicago (1,454 ft.) became the world’s tallest from 1974-1988. The Petronas Towers in Malaysia (1,476 ft.) have been the tallest buildings in the world since then. Currently under construction, Taiwan’s Taipei Financial Center (1,667 ft.) will be the world's tallest building upon completion in 2003.

    Early skyscrapers had to be built on solid bedrock because they were so heavy. This is one reason why so many were built on Manhattan, a rocky island in New York City. The bedrock there is relatively close to the surface, especially at the lower end. Skyscrapers also provided a solution to the high cost of land in the city.

    WTC “Twin Tower” Facts

  • Minoru Yamasaki, the architect who designed the WTC, was the son of Japanese immigrants.
  • The WTC project was controversial at first and a lot of people didn’t like the idea.
  • The Twin Towers were not identical. Tower One (a.k.a. the North Tower) was six feet taller than Tower Two (a.k.a. the South Tower). The North Tower also had a 360-ft.-high radio antenna on top, while Tower Two had an observation deck.
  • The twin towers were the first super-tall buildings designed without any masonry.
  • The Twin Towers were so tall that they could cast a two-mile long shadow!
  • 18 ¾”-wide exterior support columns were set only 22" apart, so the windows were like narrow slits. The overall effect, as seen from a distance, looked like the towers had no windows at all.
  • Worried that intense air pressure created by the buildings' high speed elevators might buckle conventional shafts, engineers designed a solution using drywall fixed to the reinforced steel core.
  • The “hollow tube” design of closely spaced steel columns, as well as the central core and elevator system, were all innovative structural designs.
  • The buildings’ excavation took 2 years, removing more than 1.2 million cubic yards of earth and rock. It created 23 acres of new land along the Hudson River waterfront, now Battery Park City.
  • The world’s highest restaurant, Windows on the World, occupied the 107th floor.
  • 1.8 million people per year visited the Top of the World observation deck in Tower Two.
  • More than 100,000 people could occupy the Twin Towers at the same time. They were so large that each tower was like a city in itself—and each one had its own individual postal zip code.
  • The Twin Towers became the "stars" of many movies and TV shows.
  • When the WTC was first built, a skydiver jumped from a plane onto the roof of Tower Two. A few days later, a parachutist leaped off the top of Tower One, landing safely in the plaza below.
  • On August 4, 1974, Frenchman Philippe Petit walked and danced across a tightrope stretched between the roofs of the Twin Towers—the highest high-wire act ever!
  • On May 26, 1977, George Willis scaled up the side of the WTC tower using homemade clamps to grab onto the building—and no rope or safety net! He reached the top in 3 ½ hours.
  • Businesses with offices inside the WTC building represented 26 different countries.
  • On February 26, 1993, a terrorist bomb exploded in the WTC basement, killing six and injuring more than 1,000 people. The WTC was closed for a month during the investigations and repairs.
  • On September 11, 2001, a Boeing 767 crashed into One World Trade Center (the north tower) at 8:45 am. Then at 9:03 am, another Boeing 767 crashed into Two World Trade Center (the south tower). The resulting fires weakened the buildings’ infrastructure. The south tower collapsed at 10:05 am, and the north tower collapsed at 10:29 am, New York time.
  • This wasn’t the first time a plane crashed into a famous skyscraper. On July 28, 1945, an American B-25 bomber came out of some low clouds and flew right into the side of the Empire State Building. The three crew members and eleven people on the 79th floor were killed, but the damage was inconsequential and was repaired within weeks.
  • The Skyscraper Museum, in collaboration with The New York Historical Society, had created an exhibition called “WTC: Monument” to commemorate the building's 30th birthday and its transition from public to private ownership. A series of programs were to have been presented by the museum at the World Trade Center in the Fall of 2001. Unfortunately, the events of September 11 necessitated a change in plans, as well as the inclusion of a tragic, final chapter.

    The World’s Oldest Skyscraper—Not!

    The Tower of Babel was an ancient Babylonian structure that would have been the world’s oldest skyscraper. “Come, let us build ourselves a city, with a tower whose top is in the heavens, so that we may make a name for ourselves.” (Genesis 11:4) In reality, the tower probably only had seven stories. God had looked down at the arrogant men who were building it, and confused them by making everyone speak in different languages; therefore the tower remained unfinished.

    Recommended Books

    America’s Top 10 Skyscrapers, by Edward Ricciuti, 1998. (Everything you want to know about America’s most unique and amazing landmark buildings, written for young readers.)

    Building Big, by David Macaulay, 2000. (This companion book to the PBS series contains a chapter on skyscrapers, and features Macaulay’s descriptive text and detailed line drawings.)

    Into the Sky, by Ryan Ann Hunter, 1998. (This colorful, informative picture book about how skyscrapers are built will be enjoyed by even the youngest architects.)

    Skyscrapers (Kids Discover series), 1994. (A popular back issue in the Kids Discover magazine series, it’s full of interesting information, amazing facts, fun photos, and related activities.)

    Skyscrapers, by Judith Dupre, 1996. (A history of the world’s most famous skyscrapers.)

    Skyscrapers! Super Structures to Design & Build, by Carol A. Johmann, 2001. (A cartoon-like introduction to skyscrapers, with hands-on activities for kids.)

    Tonka: Building the Skyscraper, by Justine Korman, 1999. (A child’s-eye view of how a skyscraper is designed and constructed, from the ground up.)

    Unbuilding, by David Macaulay, 1987. (Fictional story of the dismantling and removal of the Empire State Building, with factual information about the building’s history and structure.)

    The World Trade Center: A Tribute, by Bill Harris, 2001. (The author deftly weaves together the architectural, cultural, political, and financial history of the World Trade Center with over 120 magnificent photos, and a tastefully done final chapter about its untimely demise.)

    Understanding September 11, by Mitch Frank. (Written especially for kids and illustrated with lots of photos and maps, a Time magazine reporter answers questions about 9/11’s tragic events.)

    Recommended Websites (The world’s largest database on skyscrapers and tall structures; includes news, facts, statistics, building materials, technical data, dates, photos, building sketches, etc.) (This website contains a pictorial timeline of the world’s tallest buildings, as well as links to articles of historical and analytical interest regarding the World Trade Towers.) (A pictorial history of the World Trade Center in New York, from the World Trade Center Association.) (PBS's companion site to the NOVA episode "Why the Towers Fell," that was broadcast on April 30, 2002. Follow a team of forensic engineers during their investigation into the Twin Towers' collapse. Hear a survivor’s story, watch a video, explore the structure of metal, read letters from structural engineers and eyewitnesses, and much more.) (Remembering September 11th: links, lesson plans, and classroom activities for students and teachers.) (September 11 archived news, timelines, photos, and mysteries.) (The World Trade Center rendered in 3-D computer graphics.) (Make your own model of the World Trade Center. All you need is a computer printer and some cardstock.) (Empire State Building Virtual Tour: go from the Art Deco lobby all the way up to the very top, and learn interesting facts about the building’s history.)


    These pages are a continuous work in progress.
    Copyright © 2000- by Teri Ann Berg Olsen
    All rights reserved.


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