The World Trade Center, designed by Minoru Yamasaki and Emery Roth, was completed in 1973 after seven years of construction, at a cost of $750 million. It opened for business in 1975.
The trade center is owned by the Port Authority of New York and New Jersey, a bistate public works agency created in the 1920s by special charter in Congress. The agency's members are appointed by the governors of New York and New Jersey.
Though the two towers were the best known part of the complex, and Manhattan's skyline, the World Trade Center actually consisted of seven buildings, including the Marriott WTC hotel, the commodities exchange at 4 World Trade Center, the U.S. Customs House at 6 World Trade Center and the Tishman Center at the 47-story 7 World Trade Center, which also collapsed yesterday after the terrorist attacks.
Occupying 16 acres in lower Manhattan, the center was the world's largest commercial complex.
One World Trade Center was 1,368 feet tall; Two World Trade Center was 6 feet shorter. At 110 stories each, the Twin Towers were the world's tallest buildings until 1974, when Chicago's 1,450-foot Sears Tower was completed. The Petronas Towers in Kuala Lumpur, Malaysia, at 1,483 feet, are now the world's tallest buildings.
The World Trade Center had 435 tenants, employing 40,000 office workers.
On Feb. 26, 1993, a terrorist car bomb exploded in the parking garage, killing six people and injuring more than 1,000. Damages were estimated at $300 million.
On Oct. 1, 1995, Sheik Omar Abdel-Rahman and nine other militants were convicted on charges related to the bombing. On Jan. 8, 1998, Ramzi Yousef was convicted of the bombing and sentenced to life in prison.
On June 8, 1999, Mayor Rudy Giuliani opened a $13-million emergency crisis center on the 23rd floor of 7 World Trade Center, near the Twin Towers. The command center was designed to coordinate responses to emergencies such as storms, blackouts and terrorist attacks.
In July of this year, in a move to privatize the operations of the World Trade Center, the Port Authority turned the center over to Silverstein Properties Inc. and Westfield America Inc. The companies paid $3.2 billion for a 99-year lease of 10 million square feet of office and retail space.
One report said Silverstein provided a $616-million down payment on the deal. However, it was not clear yesterday if the deal had been legally finalized and what the financial repercussions would be for the Port Authority, the city or the state.
Several other parts of the complex, including the Marriott Hotel in 3 World Trade Center, the U.S. Customs House in 6 World Trade Center and the building known as 7 World Trade Center, are already under long-term leases.
Albany Bureau Chief Jordan Rau and Reuters contributed to this story.