Town (pop., 2000: 11,909), north-central New Mexico, U.S. It lies on the Pajarito plateau of the Jemez Mountains, northwest of Santa Fe .
The site was chosen by the U.S. government in 1942 as the location for the Manhattan Project , which developed the first atomic bomb . After World War II, the Los Alamos Scientific Laboratory developed the first nuclear fusion bomb. The town was built to house laboratory employees; it is still the site of a major nuclear research facility.