Unidentified Photographer, [Burned-over landscape north of ground zero in the vicinity of Hiroshima Castle], October 31, 1945 (2006.1.278)
4H, GZ3200. Looking southeast from Hiroshima Castle. Shows group of unburned blast-destroyed, combustible buildings 3,200 feet northeast from GZ (3,700 feet from AZ) in old castle grounds. Surrounding area completely devastated by blast and fire. Hiroshima: Ground Zero, 1945,p. 115.
Unidentified Photographer, [Ruins of Geibi Bank Company, Kyobashi branch, Hiroshima], November 12, 1945 (2006.1.158)
5J, GZ5900. Looking northeast at Building 110, the roof of which was structually damaged by blast. Note bent fire shutters on windows; open nonautomatic fire door (combustible building adjoined). Hiroshima: Ground Zero, 1945,p. 165.
Unidentified Photographer, [Blast-damaged Motomachi Water Station and bicycles, Hiroshima Water Department], November 19, 1945 (2006.1.367)
Building 63. 5H, GZ1800. Motomachi Water Station, Hiroshima Water Department. Building N, 1,800 feet east of GZ, looking north. A steel frame, noncombustible repair shop structurally damaged by blast. Drill press and lathe seriously damaged by fire in combustible floor and contents. Note rubber tires and bicycles burned. Hiroshima: Ground Zero, 1945,p. 71.
Unidentified Photographer, [Superficially blast-damaged stell-frame with fire-damaged tools, Isudashiki Pump Factory, Hiroshima], November 19, 1945 (2006.1.368)
Building 83, AKA Building P: Isudashiki Pump Factory. 4G, GZ3300. Building P, 3,300 feet northwest of GZ, looking east. A steel frame, combustible, light-engineering shop superficially damaged by blast. No damage to machine tools by blast or debris. Serious damage to all machines by fire in combustible debris and wood floor. Entire congested area burned over. Hiroshima: Ground Zero, 1945,p. 105.
United States Government, The United States Strategic Bombing Survey: Physical Damage Division, The Effects of the Atomic Bomb on Hiroshima, Japan, Volume II, May 1947, pp.96-97 (2011.23.2)
Definition. The zero point may be defined as the point of detonation of the atomic bomb. The point had location in plan and elevation, inasmuch as the bomb burst in the air. Throughout this report the ground location of the point immediately under the burst is designated as ground zero, abbreviated to GZ, and the actual point of detonation in the air is designated as air zero, abbreviated to AZ. Hiroshima: Ground Zero, 1945,p. 18.