People of Wartime Los Alamos

Throughout the summer of 1943, hundreds of bewildered families moved to Los Alamos to begin an unforgettable adventure. Scientific personnel had only a very general idea about the nature of the work that awaited them. They were instructed to tell their families nothing. Most administrative and technical personnel knew only that they were moving to an unknown place for an unknown length of time.

http://www.lanl.gov/history/wartime/index.shtml