Chicago Pile No. 1

Chicago Pile No. 1 (CP-1) was the world's first experimental nuclear reactor, achieving the first self-sustaining nuclear chain reaction on December 2, 1942. Constructed under the supervision of physicist Enrico Fermi at the University of Chicago, CP-1 was a graphite cube with uranium slugs and oxide lumps. This groundbreaking achievement demonstrated the feasibility of controlled atomic energy release, paving the way for both nuclear power and the development of atomic weapons during the Manhattan Project. CP-1 operated at low power for experimental purposes and was later moved and decommissioned in 1953.123