9/11 Photos: Then and Now

(Left) New Yorkers walk over the Brooklyn Bridge on their way to work, April 7, 1980, during the transit strike. (Right) People flee the scene of the attacks on the World Trade center on September 11, 2001.

(Left) The Brooklyn Bridge is seen spanning over New York's East River, with the twin towers of the World Trade Center in the background, June 12, 1990. (Right) Smoke rises behind the Brooklyn Bridge over the East River, and frames the skyline of Manhattan, minus the World Trade towers, the day after hijacked airplanes crashed into both buildings causing their collapse.

(Left) Daniel Goodwin ("Spider Man") climbs the sheer face of the North Tower of the World Trade Center in Manhattan, New York City on May 30, 1983. (Right) Smoke pours out of the World Trade Center after an air plane struck the buildings on Tuesday morning, September 11, 2001.

(Left) New York's Empire State Building is illuminated at sunset in the colors of the British flag in honor of Princess Diana Thursday, Sept. 4, 1997. (Right) In a horrific sequence of destruction, terrorists crashed two planes into the World Trade Center causing the twin 110-story towers to collapse on September 11, 2001.

Cleanup and recovery efforts continue in this overall view at the site of the World Trade Center disaster.

(Left) This general view shows the World Trade Center twin towers as construction continues on the buildings at Church Street between Vesey and Liberty Streets in lower Manhattan, New York City, on Jun 13, 1970. (Right) This photo taken by the New York City Police Department shows smoke and ash engulfing the area around the World Trade Center in New York.

(Left) The Statue of Liberty and the New York skyline frame warships and smaller craft for Operation Sail in this helicopter view on Saturday, July 3, 1976. (Right) Thick smoke billows into the sky from the area behind the Statue of Liberty, lower left, where the World Trade Center towers stood, on Tuesday, September 11, 2001. The towers collapsed after terrorists crashed two planes into them.

(Left) A destroyed subway station near ground zero on the evening of September 12, 2001 after the September 11 terrorist attacks on the World Trade Center in New York City.(Right) Pedestrians walk along Church St. in lower Manhattan, Aug. 4, 2011 in New York. Behind them is the tower known as Four World Trade Center.

(Left) Emergency workers at ground zero on September 11, 2001 after the terrorist attacks on the World Trade Center in New York City.(Right) Pedestrians walk along Church St. past Century 21 clothing store in lower Manhattan, Aug. 4, 2011, in New York.

(Left) Medical and emergency workers, who are standing in front of the Millennium Hilton, look towards where the World Trade Center towers used to be, after a terrorist attack on the twin towers of lower Manhattan. (Right) Pedestrians pass the Hilton Hotel on Church St. in lower Manhattan, Aug. 4, 2011, in New York.

(Left) The World Trade Center destruction is shown in the aftermath of the September 11 attacks in New York. (Right) The tower known as Four World Trade Center is under construction in lower Manhattan, Aug. 9, 2011 in New York.

(Left) Pedestrians flee the area of the World Trade Center as the center's south tower collapses following a terrorist attack on the New York landmark. (Right) Activity on Park Row is shown in lower Manhattan, Aug. 4, 2011 in New York.

(Left) The south tower starts to collapse as smoke billows from both buildings of the World Trade Center in New York. (Right) The skyscraper known as One World Trade Center rises in the lower Manhattan skyline, Aug. 4, 2011 in New York

(Left) Smoke rises into the sky following the collapse of World Trade Center Towers in New York. (Right) The skyscraper known as One World Trade Center rises in lower Manhattan, Aug. 10, 2011 in New York