Mrs. Jacqueline Kennedy places flowers on President Kennedy's grave at Arlington National Cemetery, on March 16, 1967, after a ceremony following re-interment of the body of President John F. Kennedy to the permanent grave site. (Cecil Stoughton. United States Army Signal Corps)

Mrs. Jacqueline Kennedy places flowers on President Kennedy's grave at Arlington National Cemetery, on March 16, 1967, after a ceremony following re-interment of the body of President John F. Kennedy to the permanent grave site. (Cecil Stoughton. United States Army Signal Corps)