was there any structure made in the memories of the deceased?
Yes a  white marble Wall of Names was dedicated
United Airlines Flight 93
2009, an agreement was announced between the landowners and the National Park Service to allow the purchase of land for $9.5million. The memorial area with a white marble Wall of Names was dedicated on September 10, 2011, the day before the 10th anniversary of the crash. A concrete and glass visitor center was opened on September 10, 2015 on a hill overlooking the memorial, with both the visitor center and the Wall of Names being aligned with the flight path and the final piece, the "Tower of Voices", was dedicated during a ceremony on September 9, 2018.
where did the 3rd plane crash on 911 It crashed into a field in Somerset County, Pennsylvania who hijacked it? By four al-Qaeda terrorists on board what was the flight's real target? Since it never reached a target, the exact place intended to be hit by Flight93 has never been decisively confirmed
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United Airlines Flight 93 [SEP] Memorials
On August 9, 2007, a portion of U.S.219 in Somerset County, near the Flight 93 National Memorial, was co-signed as the Flight 93 Memorial Highway. At the National September 11 Memorial, the names of the victims of Flight93 are inscribed on Panels S-67 and S-68 at the South Pool. On the sixteenth anniversary of the crash, Vice President Mike Pence spoke at the memorial: "Without regard to personal safety, they [the victims] rushed forward to save [our] lives... I will always believe that I and many others in our nation's capital were able to go home that day and hug our families because of the courage and sacrifice of the heroes of Flight93."