Los Alamos National Laboratory

Los Alamos National Laboratory sits on a high mesa in northern New Mexico, the site chosen in 1943 for the Manhattan Project's secret weapons laboratory, where the first atomic bombs were designed under J. Robert Oppenheimer. So classified that the town did not officially exist and residents shared a single post-office box, it remains one of the nation's premier — and most restricted — nuclear and national-security research laboratories.

• New Mexico
  The Land of Enchantment, high desert and southern Rockies related
• Trinity Site
  Where the first atomic bomb was detonated related