Los Alamos
Los Alamos was a classified research laboratory site, built as part of the Manhattan Project to develop an atomic bomb, along with Oak Ridge, Tennessee, and Hanford, Washington. The site was home to a “secret city” built to accommodate thousands of scientists, engineers, and their families.
On July 16, 1945, the world's first nuclear explosion occurred when a plutonium implosion device was detonated at a site located 210 miles south of Los Alamos, in New Mexico.