United States v. Lee (1882)
With local cemeteries in Alexandria County and Alexandria filling rapidly with war dead, Quartermaster General of the United States Army Montgomery C. Meigs proposed using of the Arlington estate as a cemetery. The first burial there was made on May 13, 1864. United States Secretary of War Edwin M. Stanton approved the establishment of a military cemetery on June 15, 1864, creating Arlington National Cemetery. By the end of the war in April 1865, more than 16,000 people had been buried at Arlington. In September 1866, a memorial and a burial vault (containing the remains of 2,111 U.S. and Confederate soldiers who died at the First Battle of Bull Run, Second Battle of Bull Run, and along the Rappahannock River) were buried in Lee's former wildflower garden on the mansion's east side beneath the Civil War Unknowns Monument, a memorial to honor unknown soldiers who had died during the American Civil War.
Arlington National Cemetery
With more than 400,000 interments, the cemetery has the second-largest number of burials of any national cemetery in the United States. The largest of the 130 national cemeteries is the Calverton National Cemetery, on Long Island, near Riverhead, New York, which conducts more than 7,000 burials each year.
In addition to in-ground burial, the cemetery also has one of the larger columbaria for cremated remains in the country. Four courts are currently in use, each with 5,000 niches. When construction is complete, there will be nine courts with a total of 50,000 niches; capacity for 100,000 remains. Any honorably discharged veteran is eligible for inurnment in the columbarium, if s/he served on active duty at some point in her/his career (other than for training).