Reactor B Monumento Histórico Nacional
In a remote corner of the Tri-Cities, shielded by desert and guarded fences, the world’s first full-scale plutonium production reactor came to life. B Reactor wasn’t just a scientific marvel, it was a keystone of the atomic age.
The World’s First Plutonium Production Reactor
Constructed in record time in 1944, B Reactor was the centerpiece of the Hanford Site and a cornerstone of the Manhattan Project. At the time of its creation, few outside the highest levels of government knew what it was for, and even most of its workers didn’t realize they were
helping create the material for the atomic bomb dropped on Nagasaki.
Designed by some of the world’s leading engineers and scientists, the reactor was a bold experiment in both scale and secrecy. It remained operational for decades after the war and now stands preserved as part of the Manhattan Project National Historical Park.
Visitors today can walk through its control room, view the iconic faceplate, and stand inside the facility that once powered the most secretive scientific mission in U.S. history.
