Atomic Heritage Foundation

In partnership with the National Museum of Nuclear Science & History

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1945 May 31

1945 May 31

Critical mass tests with plutonium begin at Los Alamos, NM.

Date Range:

1945CE May 1st

Era:

1945: Building the Bomb

Hear the stories of the Manhattan Project

Browse our collection of oral histories with workers, families, service members, and more about their experiences in the Manhattan Project.

Tour the Sites of the Manhattan Project

Tour some of the key locations of the Manhattan Project with an audio guide.

Read recent news & articles

Secretary of DOI Sally Jewel and of DOE Ernie Moniz shake hands on launching the new park as a partnership between their two agencies.

5th Anniversary of the Manhattan Project National Historical Park

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