On Sunday, the incredible 'Tower of Voices' memorial was unveiled at the Pennsylvania crash site of Flight 93 to honor the heroic passengers who fought to keep the hijacked plane from reaching its target on September 11, 2001.
The tower is 93 feet tall, and features aluminum wind chimes -- each with its own unique sound -- for each of the plane’s 40 passengers. It serves as the final component of the Flight 93 National Memorial at the crash site.
You can listen to the tower's first chimes below.
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