ARLINGTON, Va. (WJW) — A sacred place steeped in American history is opening to the public for the first time in nearly 100 years.

The Tomb of the Unknown Soldier Plaza, a spot in Arlington National Cemetery usually only the Sentinels of the 3rd U.S. Infantry Regiment (a.k.a. “The Old Guard”) is allowed to be near, is celebrating its centennial with a public flower ceremony through Wednesday.

“As the stewards of the Tomb of the Unknown Soldier, it’s our honor to lead the centennial commemoration of this site,” Karen Durham-Aguilera, executive director of Army National Military Cemeteries and Arlington National Cemetery, said in a statement.

“The Tomb has served as the heart of Arlington National Cemetery. It is a people’s memorial that inspires reflection on service, valor, sacrifice and mourning. As a sacred memorial site and the grave of three unknown American service members, the Tomb connects visitors with the legacy of the U.S. armed forces throughout the nation’s history.”

Those who wish to participate in the free event are asked to register here, but walkups are allowed. The event runs from 9 a.m. to 4 p.m. The cemetery is offering complimentary flowers to all guests to place on the Tomb if they do not have their own, and historians are set to be hand to help give background.

The event runs Tuesday and Wednesday this week. Veteran’s Day is celebrated on Thursday.