Nash Harden

In 1942, a secret city was built in Oak Ridge, Tennessee, as part of the Manhattan Project. Practically overnight, what was once farmland became a classified community with a population of 75,000.

The U.S. government acquired 59,000 acres of rural land and constructed massive facilities behind security fences. Workers lived in hastily built houses, dormitories, and trailers, yet most had no idea they were helping develop materials for the atomic bomb. The city was so secret that it didn’t appear on maps, and mail was routed through a special post office in Knoxville. Signs reminded residents: “What you see here, what you do here, what you hear here, when you leave here, let it stay here.”

Despite the secrecy, Oak Ridge functioned like a real town, complete with tennis courts, skating rinks, bowling alleys, and theaters to keep morale high. The average age of its residents was just 27, as many young scientists moved in with their families.

It wasn’t until 1945, when the first atomic bomb was dropped, that Oak Ridge’s residents learned the true nature of their work. The uranium they had helped enrich was used in the “Little Boy” bomb, which was dropped on Hiroshima.