Hanford Site (Wikipedia)
The Hanford Site is a decommissioned nuclear production complex operated by the United States federal government on the Columbia River in Benton County in the U.S. state of Washington. It has also been known as Site W and the Hanford Nuclear Reservation. Established in 1943 as part of the Manhattan Project, the site was home to the Hanford Engineer Works and B Reactor, the first full-scale plutonium production reactor in the world. Plutonium manufactured at the site was used in the first atomic bomb, which was tested in the Trinity nuclear test, and in the Fat Man bomb used in the bombing of Nagasaki.- B Reactor (Wikipedia)
The B Reactor at the Hanford Site, near Richland, Washington, was the first large-scale nuclear reactor ever built. The project was a key part of the Manhattan Project, the United States nuclear weapons development program during World War II. Its purpose was to convert natural (not isotopically enriched) uranium metal into plutonium-239 by neutron activation, as plutonium is simpler to chemically separate from spent fuel assemblies, for use in nuclear weapons, than it is to isotopically enrich uranium into weapon-grade material. The B reactor was fueled with metallic natural uranium, graphite moderated, and water-cooled. It has been designated a U.S. National Historic Landmark since August 19, 2008 and in July 2011 the National Park Service recommended that the B Reactor be included in the Manhattan Project National Historical Park commemorating the Manhattan Project. Visitors can take a tour of the reactor by advance reservation.