Antietam National Cemetery, which adjoins the park, covers and contains more than 4,976 interments (1,836 unidentified). The cemetery was commissioned in 1865, and interments began in 1867, following an arduous process of identifying the remains, which was only successful in about 40% of the cases. Civil War era burials in this cemetery consist of only Union soldiers; Confederate dead were interred in the Washington Confederate Cemetery in Hagerstown, Maryland; Mt. Olivet Cemetery, in Frederick, Maryland; and Elmwood Cemetery in Shepherdstown, West Virginia. The cemetery also contains the graves of veterans and their wives from the Spanish–American War, both World Wars, and the Korean War. The cemetery was closed to additional interments in 1953. However, two exceptions have been made; the first in 1978 for Congressman Goodloe Byron and the second in 2000 for the remains of USN Fireman Patrick Howard Roy who was killed in the attack on the USS "Cole". The cemetery was placed under the War Department on July 14, 1870; it was transferred to the National Park Service on August 10, 1933. The gatehouse at the cemetery entrance was the first building designed by Paul J. Pelz, later architect of the Library of Congress.