SHANKSVILLE, Pa. -- With the word's "let's roll," U.S. Interior Secretary Ken Salazar and relatives of United Flight 93 victims turned shovels of dirt at a groundbreaking ceremony Saturday for a permanent national memorial at the Somerset County crash site.

The memorial is set to open by Sept. 11, 2011, the 10th anniversary of the terrorist attacks.

Gordon Felp of the Families of Flight 93 said Saturday the victims' courage inspired people to work on the project.

The 2,200 acre park will feature a chapel with 40 chimes symbolizing each of the victims at its entryway. A path will guide visitors to the crash site.

The plane was traveling from Newark, N.J., to San Francisco when it was diverted by hijackers with the likely goal of crashing it into the White House or Capitol.

Pennsylvania Gov. Ed Rendell said, "They were bonded by sense of urgency into action that changed the history of the world. And that's a lesson of patriotism and heroism that can never ever be forgotten."

The ceremony started with Rev. Paul Britton, who blessed the land.

Britton said, "We are assembled to turn this earth, making it ready for the national memorial which will rise here."

Salazar, who was the keynote speaker at the ceremony, said, "The memorial is an expression of we the people ... and the example that they showed to the entire world that the ark of moral justice will always have good triumph over evil no matter what the case."