The Clinton Engineer Works, which became the Oak Ridge Reservation, was the administrative and military headquarters for the Manhattan Project and home to more than 75,000 people who built and operated the city and industrial complex in the hills of East Tennessee.
The Oak Ridge Reservation included three parallel industrial processes for uranium enrichment and experimental plutonium production.
The Oak Ridge site includes
• X-10 Graphite Reactor National Historic Landmark, a pilot nuclear reactor which produced small quantities of plutonium;
• Buildings 9731 and 9204-3 at the Y-12 complex, home to the electromagnetic separation process for uranium enrichment;
• K-25 Building site, where gaseous diffusion uranium enrichment technology was pioneered. Buildings 9731, 9204-3 and K-25 together enriched a portion of the material for the uranium bomb.