In some ways, Oak Ridge was an ordinary Tennessee town in the 1940s, albeit one whose inhabitants were almost entirely employed by the US military. But the tens of thousands of workers inside the gated community were focused on one thing: the Manhattan Project, which culminated in the dropping of the atomic bombs in Japan. As the site's only authorized photographer, Ed Westcott chronicled the history of Oak Ridge from its start in 1942 through the post-World War II years, documenting the vast computer rooms and laboratories, the propaganda posters, and the everyday lives of people in the "Secret City." Now, several of these photographs are available over at The Atlantic. As America struggles to deal with its nuclear legacy, Westcott himself still lives in Oak Ridge: he recently celebrated his 90th birthday there.