A memorial opened on Sunday, dedicated to passengers and crew killed when a hijacked plane was crashed into a rural Pennsylvania field on September 11, 2001.

The Tower of Voices stands 93 feet tall and includes a unique wind chime for each of the 40 who died in the crash.

Pennsylvania Gov. Tom Ridge said at the dedication the chimes in the tower will provide "an everlasting concert by our heroes."

SHANKSVILLE, Pa. (AP) — A tower that honors the passengers and crew killed when a hijacked plane was crashed into a rural Pennsylvania field is now in place, the final major feature of a 2,200-acre memorial.

The Tower of Voices was dedicated Sunday, with remarks from former Pennsylvania Gov. Tom Ridge and the park's superintendent.

The wind chimes inside the Tower of Voices. bioLinia and Paul Murdoch Architects via National Park Service

The 93-foot structure at the Flight 93 memorial north of Shanksville is designed with a wind chime for each of the 40 who died on Sept. 11, 2001.

Ridge, who became the first head of the federal Homeland Security Department, said the chimes, each of which is tuned and positioned to give it a distinct sound, will provide "an everlasting concert by our heroes."

Three other hijacked planes were crashed into the World Trade Center in New York and the Pentagon. Nearly 3,000 people died in the attack.

People attending the dedication stand around the 93-foot tall Tower of Voices on Sunday, Sept. 9, 2018 at the Flight 93 National Memorial in Shanksville, Pa. AP Photo/Keith Srakocic

President Donald Trump is expected to attend the 17th anniversary event at the Pennsylvania site on Tuesday.

The Flight 93 National Memorial north of Shanksville already includes a memorial plaza, dedicated on the 10th anniversary in 2011, and a visitor's center that opened three years ago.