The "Tower of Voices" features 40 wind chimes representing each victim who died September 11, 2001 on United Flight 93.
원문출처 : https://www.cnn.com/videos/us/2018/09/10/tower-of-voices-united-flight-93-memorial-pennsylvania-orig-llr.cnn
원문출처 : https://www.cnn.com/videos/us/2018/09/10/tower-of-voices-united-flight-93-memorial-pennsylvania-orig-llr.cnn