Today marks the 17th anniversary of the 911 attack on this nation, which hit New York’s iconic World Trade Center, the Pentagon, and a farm field in Shanksville, Pennsylvania.

The heroes of United Airlines flight 93, who brought down the plane before it could return to Washington D.C. and slam into the White House, are being honored with an innovative memorial.

In a field amid the rolling hills of central Pennsylvania stands the “Tower of Voices.” Ninety-three-feet tall, it honors the heroes of Flight 93.
It will be dedicated later today, the last piece of this 2,200-acre memorial that includes the crash site, known as the sacred ground; a visitor center that tells the story of Flight 93; and the wall of names built directly under the flight path.

The tower, still a work in progress, holds eight wind chimes, but soon there will be 40 – one for each passenger and crew member who died here on September 11, 2001.

The tower stands at 93 feet, for the flight number. There are 40 chimes, each one representing a life taken by the four terrorists who hijacked the plane. The chimes are the final phase of the memorial’s construction, and the piece will stand close to the entrance of the site.

The final installation is as much work of land art as memorial: A visitor’s center of permanent and temporary exhibits sits at the edge of a giant bowl-like field that looks out at the impact site. From there, a one-mile-long path winds along the edge of the bowl with a long, sloping black wall that marks the edge of the crash site. In the distance are the fields and woods where the final remains of the passengers and crew members rest. Beyond the site sits a hemlock grove damaged by the crash, as well as a giant rock that marks the impact site. Only family members are allowed to enter the field.

As the visitors’ path winds its way along the edge of the field, benches offer places of contemplation, and there are also places to leave personal offerings. Finally, there is ‘The Wall of Names,’ a series of forty white marble panels each inscribed with the name of a murdered passenger or crew member. The wall leads to a wooden ceremonial gate where visitors can stand and look down the actual flight path to the impact site.

The design was inspired by the desire to add the sense of hearing as an approach to memorializing the victims.

Architect Paul Murdoch, the mind behind the Flight 93 National Memorial, says it’s the voices of the 40 passengers and crew members aboard the downed United Airlines plane that linger with him. That’s why his proposal for the 2,200-acre National Park Service-operated site called for not one but two phases. First came the Wall of Names, etched in white marble. Now, the Tower of Voices, a 93-foot-tall precast concrete structure with 40 of the world’s largest chimes.

“It starts with the wind,” says Elizabeth Valmont, an acoustics expert at the design firm Arup and acoustic lead for the chimes. The tower stands sentinel over the site, she says, with 40 independent polished aluminum chimes, between 5 and 9 feet in length, nestled within. Each chime represents an individual aboard the flight, and together they engage in an eternal “conversation,” but only as the currents guide them.

Prayers are being said today, for the victims of 911 and their families.