In 1942, the U.S. government snapped up more than 60,000 acres of land in eastern Tennessee as part of the Manhattan Project.
The area, called Oak Ridge, was already home to about 3,000 people. But for the next seven years, the town remained top-secret while thousands of federal workers developed materials for the atomic bomb. Residents were required to wear badges when outside their homes and armed guarded were staked at all the city's entrances.
The U.S. Department of Energy recently digitized hundreds of 1940s-era photos of the "secret city." Although many of the photos are posed, they provide a snapshot of life during a monumental period in U.S. history.
[via A Continuous Lean]
Thousands of people from all over the country who were brought in to work at the site lived in housing developments.
By 1945, the population of Oak Ridge grew from 3,000 to 75,000.
Here's a typical "Flat-Top" housing structure.
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