Site X was a town that didn’t exist, a city so top secret it couldn’t be listed on any map in America. People who lived in the town pledged to never talk about their work, not even with their husbands or wives. Even the people who lived at Site X didn’t exactly know what they were doing at their jobs. They just knew that they were working on a project that could end the war and help the Allies defeat Hitler and Japan. Site X was located in the valley of the Clinch River near Knoxville, TN, and was home to a critical part of the top secret Manhattan Project. Secretaries, factory workers, nurses, new high school graduates, and college students were given lie detector tests they had to pass before they were hired to work in the secret city. After the war, the residents learned that there two other secret cities built in the US.