At 251 p.m. on Oct. 19 1970 the World Trade Center became the worlds tallest building when a 38-foot-tall wall section was placed atop the 100th floor. This section stretched from the 100th to the 103rd floors reach
A view of the World Trade Center and the West Side waterfront on July 12_1971. The north tower (Tower 1) was completed in December 1972 and the south tower (Tower 2) in July 1973
The World Trade Center looking south on July 12, 1971. The construction project involved excavating a large amount of material, which was later used as landfill to build Battery Park City in Lower Manhattan
Topping out the south tower, in a photo taken from the 104th floor of the north tower, on July 19, 1971.
Steel heads up to top out the south tower.
The twin towers on April 3, 1973, the day before the dedication.
A duplicate view of the World Trade Center as seen from the Empire State on Nov. 29, 1973.
Philippe Petit, the French aerialist, managed to bring the towers to human scale when he walked between them on a tightrope on Aug. 7, 1974.
Diana Byar and Ralph Braw of the Battery Dance Company performing for a lunchtime crowd on the plaza in June 1982.
The passenger liner Queen Elizabeth 2 arrived on July 19, 1982, after completing a trans-Atlantic crossing.
The ground excavated for the World Trade Center became Battery Park City. Bare landfill formed a beach in July 1983.
July 4 1986.
Windsurfers in New York Harbor competed in a qualifying round for the United States Boardsailing Association championships in 1990.
Early-morning fishermen on the Caven Point Pier off Port Liberté in Jersey City tried their luck in the harbor in 1993.
The observation deck on the 107th floor in 1994. Roko Camaj a window washer tended to the only windows on the World Trade Center that required hand cleaning all the others were cleaned by machine. Mr. Camaj was killed on Sept. 11- 2001.
The half-price tickets booth in 2 World Trade Center in 1997.
The Greatest Bar on Earth on the 107th floor of the north tower in 1997.
A full moon alongside the World Trade Center at sunset in 1997.
Bob Demeusy, sitting, and Bob Hoffman of CBS News climbed even higher than the observation deck to install a camera in 1997.
Newlyweds, married on Valentine's Day 1999 on top of 2 World Trade Center. Thirty other newlywed couples visited that day.
A tourist photographed a Christmas tree atop the World Trade Center
Visitors looked out at the panorama of Manhattan from the 107th floor of the south tower on a crisp cloudless December morning in 2000
At 8-46 on the morning of Sept. 11 2001 hijackers sent an American Airlines jet into the north tower right. Shortly after 9 a.m. a United Airlines jet hit the south tower
The fireball in the south tower.
Though nearly 3,000 people died in the attacks in New York, Pennsylvania and Washington tens of thousands of workers safely escaped the World Trade Center that day.
People looking out of the burning north tower.
Trapped in the burning towers some people jumped.
Pedestrians on Park Row fled as the south tower collapsed.
A woman watched the first building come down her neighbor could not bear to look.
The north tower.
Pedestrians hurried through the smoke and soot that dispersed downtown after the collapse of the twin towers.
The term ground zero borrowed from nuclear devastation was soon applied to the site of the towers.
The Rev. Mychal F. Judge the chaplain of the New York Fire Department was fatally struck by falling debris soon after administering last rites to a firefighter at the World Trade Center on Sept. 11- 2001.
Ash and rubble was everywhere.
By 9 a.m., a couple of hundred firefighters had arrived to help rescue the injured, and hundreds of police officers and emergency workers rushed to the area as well.
Firefighters in the rubble of the collapsed World Trade Center.
Firefighters poured water on the rubble of the towers
A police officer covered in ash from the first building collapse caught his breath in the Stage Door Deli on Vesey Street.
A woman sat in shock on the curb on Church Street in front of Trinity Church.
Wednesday morning Sept. 12 2001.
A tea set photographed on Sept. 19.t.
The base of the destroyed World Trade Center. Exhausted firefighters laid on the ground.
The remnants of the center.
Smoke continued to rise on Sept. 15.
Mike Hadden, a firefighter, went on to spend hours sifting the rubble for survivors and months attending memorials for fallen comrades.
Carl Vasquez, left, Jay Robbins, center, and Dennis McLane, all emergency medical technicians at the funeral of Yamel Merino 25 who died at the World Trade Center.