United flight 93 victims photos

The National Park Service's Flight 93 National Memorial is near Shanksville, Pa.

A visitor enters the Flight 93 National Memorial Visitor Center, a stark concrete-and-glass structure set on a hill high above a meadow where the hijacked airliner crashed on Sept.

11, 2001.A

A scarred and crumpled section of Flight 93's fuselage shows the first three digits of the plane's ID number 5491 in a display at the Flight 93 National Memorial Visitor Center.

Two people inside the Flight 93 National Memorial stand at a window overlooking the 40-acre field below where United Airlines Flight 93 crashed on Sept.

11, 2001.

A 17-ton boulder in a field closed to visitors marks the spot where the hijacked airliner United Airlines Flight 93 crashed on Sept. 11, 2001, near Shanksville, Pa.

The Visitors Center at the National Parks Service's Flight 93 National