The World Trade Center site in New York is shown on the seventh anniversary of the attacks. Presidential candidates Sen. John McCain (R-Ariz.) and Sen. Barack Obama (D-Ill.) are scheduled to visit the site. (Mark Lennihan / Associated Press)
A man walks through a flag memorial at the Pentagon during a ceremony marking the seventh anniversary of the Sept. 11 attacks in Washington and New York. (Susan Walsh / Associated Press)
A member of the U.S. Navy rings a bell while the names are read of the people who were killed at the Pentagon during a ceremony to mark the seventh anniversary of a hijacked airliner slamming in the building in Arlington, Va. Today President Bush will dedicate the Pentagon Memorial to the memory of those killed in the terrorist attack. (Mark Wilson / Getty Images)
Visitors to the temporary Flight 93 memorial in Shanksville, Pa., participate in a sunrise memorial. (Gene J. Puskar / Associated Press)
A U.S. Army soldier stands at Camp Liberty in Baghdad at a ceremony to mark the seventh anniversary of the Sept. 11 terrorist attacks in the U.S. (Maya Alleruzzo / Associated Press)
People listen to the roll call of the deceased from the Trinity Church cemetery during the 9/11 remembrance ceremony in New York. (Stephen Chernin / Associated Press)
A family member attends a ceremony at Zuccotti Park in lower Manhattan commemorating the 9/11 attacks. (Timothy A. Clary / AFP / Getty Images)
Susan Vanvolkenburgh traces the name of her father, Stanley R. Hall, a passenger on American Airlines Flight 77, which slammed into the Pentagon. (Mark Wilson / Getty Images)
A man sits on a bench that honors a Sept. 11 victim after the dedication of a memorial at the Pentagon. (Gerald Herbert / Associated Press)
Flags are held at a memorial ceremony at the Pentagon. (Susan Walsh / Associated Press)
Students in Multan, Pakistan, light candles at a vigil to honor victims of the Sept. 11 attacks in the U.S. (MK Chaudhry / EPA)
