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Los Alamos County, New Mexico

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Please add profiles of those who were born in Los Alamos County, New Mexico.

Official Website

The first white settlers arrived in the 1880s, and the county, named for its seat, was established out of parts of Santa Fe and Sandoval counties in 1949; in 1969 the Los Alamos county and city governments were integrated into one government. In land area Los Alamos is the smallest county in New Mexico. The U.S. government owns more than 90 percent of the land, on which nuclear research facilities are located, and nearly 65 percent of the jobs in the county are with the federal government. Area 109 square miles.

The county is home to the Los Alamos National Laboratory. It was initially organized during World War II for the design of nuclear weapons as part of the Manhattan Project.

Adjacent Counties


Los Alamos (County Seat)

  • White Rock


Encyclopedia Britannica


Nat'l Reg. of Hist. Places

Bandelier National Monument (part)

Santa Fe National Forest (part)

Manhattan Project

Los Alamos National Laboratory