World Trade Center


A World Trade Center (WTC) brings together businesses and government
agencies involved in foreign trade. The World Trade Centers Association is
an organization of nearly 300 World Trade Centers in almost 100 countries.

World Trade Center of New York City

The World Trade Center was a complex of several buildings around a central
plaza, near the foot of Manhattan in New York City. It was designed by
American architect Minoru Yamasaki with Antonio Brittiochi, and was one of
the most striking American implementations of the architectural ethic of Le
Corbusier, as well as the seminal expression of Yamasaki's gothic modernist
tendencies. Constructed in the early 1970s under the auspices of the
semi-autonomous Port Authority of New York and New Jersey, the WTC complex
came to consist of 7 buildings, but its most notable features were the main
twin towers. On any given day, some 50,000 people worked in the towers.

Although the towers became an undeniable icon of New York City, they were
troubled in many ways. Initially conceived (as the name suggests) as a
complex dedicated to companies and organizations directly involved in "world
trade," they failed to attract the anticipated clientele; over time, various
governmental organizations became key tenants. Moreover, the immense
"superblock" plaza, which replaced a more traditional, dense-packed
neighborhood, was regarded by some critics as a inhospitable environment
that disrupted the intricate flows of traffic typical of Manhattan. For
example, in his book The Pentagon of Power, the technical historian Lewis
Mumford denounced them as an "example of the purposeless giantism and
technological exhibitionism that are now eviscerating the living tissue of
every great city." However, the spectacular views available from the WTC's
observation deck provided offered city-dwellers and tourists alike a
perspective on the region that became central to the city's identity.

The twin towers

Each of the towers had 110 stories. The heights of the towers were 417 m
(1368 feet) (tower one, the northern one with a huge antenna on top) and 415
m (1362 feet) (tower two, the southern one with a spectator platform). When
the towers were completed in 1972 (tower one) and 1973 (tower two) they were
the tallest buildings on earth, 100 feet taller than the Empire State
Building. Their size was the subject of a joke during a press conference
unveiling the landmarks. Minoru Yamasaki was asked: "Why two 110-story
buildings? Why not one 220-story building?" His response was: "I didn't want
to lose the human scale."

Another joke was that the towers looked like the boxes that the Chrysler
Building and Empire State Building came out of.

For a time the local television station on Channel 11 used the towers as a
graphic representation of its channel number.

The towers held the height record only briefly. As the building neared
completion, work had already begun on Chicago's Sears Tower, which would
climb to 1,450 feet. Since the World Trade Center's destruction, the Empire
State Building is again the tallest building in New York, after spending
almost 30 years as the third-tallest.

To solve the problem of wind sway or vibration chief engineer Leslie
Robertson took a then unusual approach - instead of bracing the buildings
corner-to-corner or using internal walls the towers were essentially hollow
steel tubes. Each tower contained 240 vertical steel columns called
Vierendeel trusses around the outside of the building, these were bound to
each other using ordinary steel trusses. In additon, 10,000 dampers were
included in the structure. With a strong shell such as this, the internal
floors could be simply light steel and concrete with internal walls not
needed for structural integrity, creating a tower that for its size was
extremely light. This method of construction also meant that the twin towers
had the world's highest load-bearing walls.

Of the 110 stories twelve were set aside for technical services, in four
three-floor areas evenly spread up the building. All the remaining floors
were free for open-plan offices.

The excavation of the foundations of the building, located on the former
Radio Row, was particularly complicated since there were two subway tubes
close by needing protection without service interruption. A six-level
basement was built in the foundations. Excavation of about 1 million cubic
yards of earth and rock created a $90 million real estate asset for the
project owner, the Port Authority of New York and New Jersey, which helped
offset the enormous loss in revenues which came from the tax breaks given to
the Trade Center itself. The spoil was used to create 23 acres of landfill
in the Hudson river next to the World Trade Center site, which became the
site of Battery Park City (still under development).

One of the world's largest gold depositories was stored underneath the World
Trade Center, owned by a group of commercial banks. The 1993 bomb detonated
close to the vault, but it withstood the explosion. One source estimates the
1993 value of the gold at one billion dollars, believed to be owned by
Kuwaiti interests. That same source claims that when the World Trade Center
was destroyed, the amount of gold "far exceed[ed] the 1993 levels." The gold
was finally recovered in its entirety in late 2001.

First Terrorist Attack

1993 World Trade Center bombing: On February 26, 1993, a bomb planted by
terrorists exploded in the underground garage of the north tower, opening a
30m hole through 4 sublevels of concrete. Six people were killed and over a
thousand injured. Six Islamic extremist conspirators were convicted of the
crime in 1997 and 1998 and given prison sentences of 240 years each.

The twin towers and 7 World Trade Center, an adjacent 47-storey building,
collapsed in a terrorist attack on September 11, 2001, when two commercial
jetliners were deliberately crashed into the twin towers. For details on
this terrorist attack: see September 11, 2001 Terrorist Attack. For details
of the tenants at the time of the attack, see One World Trade Center tenants
and Two World Trade Center tenants.