Several visible bunkers in the south base area were used to store munitions for training. Buildings to the right of the bunkers were used late in the wartime period for development of the atomic bombs Little Boy and Fat Man, as well as practice bombs called 'Pumpkins.' The tower to the west of the long buildings is not historic and was constructed for the filming of 'Independence Day.' Looking southeast, the 'Gun Butt' structure was used to test aircraft machine guns.