• 1.

    Robert Peraza, who lost his son Robert David Peraza, pauses at his son’s name at the North ...

    Robert Peraza, who lost his son Robert David Peraza, pauses at his son’s name at the North Pool of the 9/11 Memorial. (Getty)

  • 2.

    (Getty)

    (Getty)

  • 3.

    Family members visit the South Pool of the 9/11 Memorial. (Getty)

    Family members visit the South Pool of the 9/11 Memorial. (Getty)

  • 4.

    A woman cries while looking at the names inscribed at the North Pool of the 9/11 Memorial. (Getty)

    A woman cries while looking at the names inscribed at the North Pool of the 9/11 Memorial. (Getty)

  • 5.

    (Getty)

    (Getty)

  • 6.

    President Obama gets his first look at the memorial pool. (Getty)

    President Obama gets his first look at the memorial pool. (Getty)

  • 7.

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    (Getty)

  • 8.

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    (Getty)

  • 9.

    A New York City police officer salutes at the North Pool. (Getty)

    A New York City police officer salutes at the North Pool. (Getty)

  • 10.

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    (Getty)

  • 11.

    A woman touches the names of 911 victims inscribed around the North Pool. (Getty)

    A woman touches the names of 911 victims inscribed around the North Pool. (Getty)

  • 12.

    (AP)

    (AP)

  • 13.

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    (Getty)

  • 14.

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    (Getty)

  • 15.

    New York police and firefighters and Port Authority police salute during the singing of the Star ...

    New York police and firefighters and Port Authority police salute during the singing of the Star Spangled Banner at one of the entrances of 9/11 Memorial Plaza. (Getty)

  • 16.

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    (Getty)

  • 17.

    Former New York Gov. George Pataki stands with Anthula Katsimatides, who lost her brother on 9/11...

    Former New York Gov. George Pataki stands with Anthula Katsimatides, who lost her brother on 9/11. (Getty)

  • 18.

    (Getty)

    (Getty)

  • 19.

    A police officer's white-gloved hand touches names on the wall surrounding the north pool. (AP)

    A police officer’s white-gloved hand touches names on the wall surrounding the north pool. (AP)

  • 20.

    A New York City police officer (NYPD) looks out at the South Pool of the 9/11 Memorial. (Getty)

    A New York City police officer (NYPD) looks out at the South Pool of the 9/11 Memorial. (Getty)

  • 21.

    A Port Authority police officer reaches to to touch the names inscribed around the North Pool of ...

    A Port Authority police officer reaches to to touch the names inscribed around the North Pool of the 9/11 Memorial. (Getty)

  • 22.

    People carry portraits of their dead relatives as they gather at the 9/11 memorial in New York. (...

    People carry portraits of their dead relatives as they gather at the 9/11 memorial in New York. (Getty)

  • 23.

    Wally Miller, Somerset County Coroner, weeps as he is acknowledged by Congressman Mark Critz of P...

    Wally Miller, Somerset County Coroner, weeps as he is acknowledged by Congressman Mark Critz of Pennsylvania’s 12 district, unseen, during the Flight 93 National Memorial Service near the crash site of Flight 93 in Shanksville, Pa. (AP)

  • 24.

    An unidentified U.S. army soldier from 1st Squadron, 7th U.S. Cavalry Regiment based in Ft Hood T...

    An unidentified U.S. army soldier from 1st Squadron, 7th U.S. Cavalry Regiment based in Ft Hood Texas reacts during a memorial service. (AP)

  • 25.

    A woman runs her hand over one of the names inscribed on the wall by the north pool of the Sept. ...

    A woman runs her hand over one of the names inscribed on the wall by the north pool of the Sept. 11 memorial. (AP)

  • 26.

    (AP)

    (AP)

  • 27.

    Eliza Peterson holds a flag near the name of her uncle, Norman Rossinow. (AP)

    Eliza Peterson holds a flag near the name of her uncle, Norman Rossinow. (AP)

  • 28.

    (AP)

    (AP)

  • 29.

    Elba Cedeno, of Waretown, N.J. , holds a sign memorializing her partner, Catherine Theresa Smith....

    Elba Cedeno, of Waretown, N.J. , holds a sign memorializing her partner, Catherine Theresa Smith. (AP)

  • 30.

    (AP)

    (AP)

  • 31.

    Rachel White, left, of Cherry Hill, N.J. , and her aunt Dolores White, of Forest Hills, N.Y. , ho...

    Rachel White, left, of Cherry Hill, N.J. , and her aunt Dolores White, of Forest Hills, N.Y. , hold aloft a sign memorializing Rachel’s brother James Patrick White. (AP)

  • 32.

    People bow their heads in prayer during a memorial service at the Pentagon. (Getty)

    People bow their heads in prayer during a memorial service at the Pentagon. (Getty)

  • 33.

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    (Getty)

  • 34.

    Lorraine Calderon kisses the name of her uncle, Daniel Lugo, who was killed on 9/11. (Getty)

    Lorraine Calderon kisses the name of her uncle, Daniel Lugo, who was killed on 9/11. (Getty)

  • 35.

    (Getty)

    (Getty)

  • 36.

    Daniel Jones, who lost his brother, Christopher Carstenjen, holds Rebecca Moss at the site of his...

    Daniel Jones, who lost his brother, Christopher Carstenjen, holds Rebecca Moss at the site of his brother’s name on the memorial. (Getty)

  • 37.

    A wreath of flowers from the Japanese Embassy stands at the Pentagon 9/11 Memorial.

    A wreath of flowers from the Japanese Embassy stands at the Pentagon 9/11 Memorial.

  • 38.

    (Getty)

    (Getty)

  • 39.

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    (Getty)

  • 40.

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    (Getty)