Top officials resign after incorrect headstones and double burials uncovered.
It's a square mile of hallowed ground across the Potomac from Washington.
Arlington National Cemetery is the resting place of more than 320,000 Americans, many of them war heroes.
Now a Pentagon investigation has uncovered troubling problems with the plots and record keeping.
Unmarked gravesites, improperly marked graves and improper handling of cremated remains were all found.
At least 211 mistakes have been documented so far.
Two are in Section 60, an area reserved for those lost in Iraq and Afghanistan.
Salon.com revealed the scandal, detailing how in 2008 Air Force Master Sgt. Marion Grabe's cremated remains were mistakenly buried on top of other remains.
Salon reporter Mark Benjamin found the pattern of bad record keeping and improperly disturbed graves.
"Arlington officials went to bury a service member in what was supposed to be an empty grave. And guess what? There was already somebody there," he explained. "They didn't know who it was, and they covered it up with grass and they walked away."
Arlington's superintendent John Metzler has been reprimanded and will step down.
His deputy was fired.
Secretary of the Army John McHugh apologized on Capitol Hill Thursday and vowed to make immediate corrections.
A new team will take over to fix the mess.
They might have to X-ray gravesites and even dig up coffins to get a perfect roll call of Arlington's heroes.