Wendover Field began after the United States Army designated the area near Wendover as an additional bombing range, choosing a site served by the Western Pacific Railroad, lying near virtually uninhabited parts of the Great Salt Lake Desert in western Utah and eastern Nevada, and offering generally excellent year-round flying weather. Site selection and construction began in 1940, and in September 1940 the Department of the Interior transferred over 1.5 million acres to the Army Air Corps; later acquisitions brought the total to over 3 million acres, making the facility the world’s largest and finest bombing and gunnery range. The first military personnel arrived in August 1941, and after the United States entered World War II on December 8, 1941, the installation became home to more than 20,000 personnel. A major part of the gunnery range was the “Tokio Trolley,” an advanced training device north of the airfield with over 60 buildings and a system of matching gun ranges that progressed from stationary firing at stationary targets to stationary firing at moving targets and finally to moving firing at moving targets, with mounted .50 caliber guns fired from a moving rail car at speeds up to 40 miles per hour at moving targets mounted on unmanned jeeps. General Douglas McArthur praised the results by saying that Wendover gunners were the best trained in the army. Twenty-two heavy bomber crews trained at Wendover Army Air Field Base before overseas assignment, including B-17, B-24, and B-29 units serving in the European, Pacific, Mediterranean, Far East, and U.S. theaters and duties, and for a short time in 1944 fighter groups trained there with P-47 long-range fighter-bombers before that program was canceled in September to make room for Boeing B-29 Superfortresses. The 509th Composite Group began forming at Wendover in September 1944 under Colonel Paul W. Tibbets as a self-contained unit with B-29 heavy bombers, its own logistics, security, F.B.I. details, and hand-picked crews and soldiers; using the code name “Silver Plate,” linked directly to the Manhattan Project, it trained on the surrounding ranges for delivery of the first atomic weapons. Its facilities, renamed the “Technical Site” and code-named “Site W47,” were used with Los Alamos scientists to design, modify, and develop the aerial delivery technology and explosive components required for those weapons. After World War II, atomic activities were consolidated and moved to the Los Alamos area, now known through this account as the Sandia National Laboratories near Albuquerque, and some final assembly buildings at the Technical Site were quickly removed, though floors and foundations, including grounded copper-lined floors, remained. Unlike other bomber units, the 509th trained to deliver a single bomb with extremely high precision and later dropped the atomic weapons on Hiroshima on August 6, 1945, by Enola Gay, and on Nagasaki on August 9, 1945, by Bockscar; after the second mission, Japan surrendered unconditionally, ending World War II. After the war, Wendover Field continued in training, gunnery, and research use until the Air Force closed it in 1969; it was declared surplus, turned over to the State of Utah in 1972 for use as a municipal airport, deeded to the City of Wendover in 1977, and followed by Tooele County in 1998, while part of the original bombing range became the Utah Test and Training Range used extensively by the U.S. Air Force.