American flags are flying over the grave markers of service men and women across the country, who made the ultimate sacrifice.
 
President Obama laid a wreath at the Tomb of the Unknown Soldier at Arlington National Cemetery.
 
He also made his final Memorial Day remarks as the nation’s commander-in-chief.
 
In preparation, American flags were placed in front of more than 200,000 headstones and rows at Arlington National Cemetery last week.