“At the same time Hanford scientists were refining plutonium, Oak Ridge, Tennessee technologists were refining uranium.

The Manhattan Project sites lie within the boundaries of Oak Ridge National Laboratory, which puts visitors through security paces. Public bus tours venture beyond the gates weekdays from March to November, and reservations must be made in advance.

When passing through the gates, visitors must present a valid federal ID. International tourists have to stay home; only U.S. citizens are allowed to visit. Everyone, however, can learn about the site’s history in detail at the American Museum of Science and Energy, in the town of Oak Ridge, 30 minutes west of Knoxville.”

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