Toward the end of 1943, Manhattan Project scientists at a secret mountain laboratory complex at Los Alamos, New Mexico, began to see the final form of their new creations. The bombs that could reduce whole cities to radioactive rubble were so large and complex that they would have to be delivered by special bombers and specially trained crews. So secret was the training operation that the crewmen themselves weren’t told exactly what they were training to do. It was run out of a tiny border town in northwest Utah.
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