Manhattan Project National Historical Park

In 1943, as World War II raged across the globe, the United States government secretly constructed a laboratory on a group of isolated mesas in northern New Mexico. The top-secret Manhattan Project had a single military purpose—develop the world’s first atomic weapons. The success of this unprecedented government program forever changed the world.

Historic Manhattan Project Sites at Los Alamos

The Manhattan Project National Historical Park encompasses 17 sites on Los Alamos National Laboratory property and 13 sites in downtown Los Alamos, where “Project Y” was centered during World War II.

The Manhattan Project at Los Alamos
In Los Alamos, New Mexico, Manhattan Project administrators found an ideal location for the secret laboratory where they designed and built the world’s first atomic weapons.
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The Manhattan Project at Hanford
Nuclear reactors at Hanford (now the Hanford Site) produced plutonium for the Manhattan Project to fuel the first atomic test and the Fat Man atomic bomb.
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The Manhattan Project at Oak Ridge
Several massive Manhattan Project facilities at Oak Ridge enriched uranium for use in Little Boy, the atomic bomb dropped on Hiroshima, Japan on August 6, 1945.
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