Locations

A little-known operation of the Manhattan Engineering District took place behind enemy lines in occupied Europe. Code-named the “Alsos” Mission, these intelligence-gathering operations moved with the advancing Allies to learn firsthand how close Germany was to developing its own atomic weapon. Under the command of General Leslie Groves, these operations succeeded in capturing most of […]

Several sites in Iowa played an important role during and after the Manhattan Project, including the Ames Laboratory at the Iowa State University where uranium production methods were developed, and the Burlington Atomic Energy Commission Plant, where atomic weapons were first assembled by the AEC.   The Ames Project The Ames Project, as it came […]

The B Reactor at Hanford was built and operated by DuPont and was the world’s first production-scale nuclear reactor. B Reactor was the first of three plutonium reactors constructed in the 100 area during the Manhattan Project. Design of the B Reactor The design was based on the success of Enrico Fermi’s “Chicago Pile I” […]

Often overlooked, British physicists were the first to realize the feasibility of an atomic bomb and their urgings were vital to the development and success of the Manhattan Project in the United States.   Cavendish Laboratory Cavendish Laboratory at Cambridge University in England first opened in 1874 under the direction of James Clerk Maxwell, the […]

Before the war, the California Institute of Technology (Caltech) was a leading university in the fields of particle and nuclear physics. It was especially known for its experimental physicists. Many scientists who had important roles on the Manhattan Project were affiliated with Caltech, including J. Robert Oppenheimer, Richard Tolman, and Robert Bacher. In addition, a […]

Harvard University Harvard became an important center for nuclear physics research during the early twentieth century. After Ernest O. Lawrence constructed the first cyclotron at the University of California at Berkeley in 1929, Harvard physicists and engineers such as Harry Mimno, Kenneth Bainbridge, and Edward Purcell began thinking about building their own cylcotron. In 1936, the construction […]

Often overlooked, Canada played an important role in the Manhattan Project, especially during the early stages of research and development. Canada was also crucial for another reason: its Northwest Territories provided a rich source of raw uranium needed to produce the bomb’s critical mass.   Eldorado Mine In May 1930, Canadian prospector Gilbert Labine discovered […]

One of the most important branches of the Manhattan Project was the Metallurgical Laboratory (Met Lab) in Chicago. Using the name “Metallurgical Laboratory” as cover at the University of Chicago, scientists from the east and west coasts were brought together to this central location to develop chain-reacting “piles” for plutonium production, to devise methods for […]

Important Manhattan Project research was conducted at Columbia University’s Schermerhorn Hall (pictured) and Pupin Hall. World-class physicists, including Nobel Prize winners Isidor I. Rabi and Enrico Fermi, joined Columbia’s research team to investigate the relatively new science of atomic particles. Hungarian physicist Leo Szilard first realized the possibility of a nuclear chain reaction in 1933, […]

After the activation of the 509th Composite Group in December 1944, some members of the group (including members of the 393rd Bombardment Squadron, the unit’s combat squad) went to Cuba for training. At Batista Field in San Antonio de Los Baños, the group trained for a month. They worked on long-range, over-water flights, in preparation for the […]

Dayton, Ohio was another site of the secret Manhattan Project work. In July 1943, Oppenheimer assigned Charles A. Thomas the task of separating polonium for use as the initiator of the bombs. Polonium, which was discovered by physicist Marie Curie, is a peculiar, soft metal which is dangerous to inhale and very difficult to produce. […]

The Houdaille-Hershey Plant was a secret Manhattan Project site located in Decatur, Illinois that was responsible for plating the interior of pipes with a nickel-powder barrier material that could be used for the gaseous diffusion process for the enrichment of uranium. Continuing failure to develop a suitable barrier material for the gaseous diffusion process by […]

An Introduction to French Nuclear History France was the premier place for research into radioactivity decades before the development of the bomb. The process started under Henri Becquerel, who first discovered radioactivity in 1896. Marie and Pierre Curie expanded upon his findings, discovering that radioactivity is based within the atom itself, rather than molecular interaction. […]

This site “manufactured ceramic insulators in the 1940s and processed uranium fuel in the 1960s. 

From 1943 until 1945, Grand Junction, Colorado was the center of the Manhattan Project’s secret effort to mine and refine uranium ore from surrounding mills in the Colorado Plateau. By 1946, over 2,600,000 pounds of uranium oxide had been produced from Colorado Plateau material, representing 14 percent of the total uranium acquired by the MED. […]

The Gun Site (TA-8-1) was where Manhattan Project scientists and engineers developed and tested the gun-type weapon design. The design for the “Little Boy” bomb dropped on Hiroshima on August 6, 1945, was developed here. The gun design was straightforward. Basically, a “bullet” of nuclear material was fired at very high speed into a second […]

Hanford, Washington, on the beautiful Columbia River, was the site selected for the full-scale plutonium production plant, the B Reactor. Today a popular tourist desination, the Hanford Site proved crucial to the success of the Manhattan Project.  Site Selection In December 1942, the Army Corps of Engineers worked with DuPont to establish criteria for the […]

Throughout its history, the U.S. nuclear laboratory at Idaho Falls (presently known as the Idaho National Laboratory or “INL”) has been home to 52 nuclear reactors, the largest concentration of nuclear reactors in the world. Today, all but three reactors have been decommissioned, and employment levels at the lab have precipitously dropped over recent years. Nonetheless, […]

Jackson Square was the heart of Oak Ridge’s business district. Originally Town Center No. 1, the name Jackson Square was adopted in February 1945 as Oak Ridge moved away from military terminology. The site was one of five commercial shopping areas distributed across the Oak Ridge reservation. Residents frequented the square on weekends and weekdays to […]

Japan was one of the Axis powers in World War II. Its attack on Pearl Harbor, HI, on December 7, 1941 brought the US formally into the war. Japan also attacked British, Dutch, and American possessions in the Southwest Pacific around the same time. Previously, Japan had invaded Chinese territory in Manchuria in 1931, as part […]

Jersey City was home to the headquarters of the M. W. Kellogg Company, which specialized in chemical engineering projects. In 1942, the S-1 Committee tasked Kellogg with conducting research into the feasibility of the gaseous diffusion process for separating uranium isotopes. As the Manhattan Project began, Kellogg’s vice president of engineering, Percival “Dobie” Keith, took […]

The K-25 Plant in Oak Ridge used the gaseous diffusion process to enrich uranium. Gaseous Diffusion Process The K-25 plant was an enormously ambitious and risky undertaking. A mile-long, U-shaped building, the K-25 plant was the world’s largest roofed building at the time. British scientists working on the “tube alloy,” code for the atomic bomb […]

In 1918, entrepreneur Ashley Pond began an “outdoor school” at Los Alamos to provide boys a chance to gain health, strength and self-confidence. The Los Alamos Ranch School combined a rigorous outdoor experience with a college preparatory education. The Los Alamos Ranch School comprised 54 buildings: 27 houses, dormitories, and living quarters totaling 46,626 sq. […]

Los Alamos, New Mexico, was the site of Project Y, or the top-secret atomic weapons laboratory directed by J. Robert Oppenheimer. The site was so secret that one mailbox, PO Box 1663, served as the mailing address for the entire town. The mountains allowed the scientists ample opportunity to relax, by skiing, swimming, and hiking. […]

A surprising number of New York City offices, laboratories, and warehouses were involved in the top-secret project. While these New York City sites remain largely unmarked and unknown, they were a small but crucial part of the success of the Manhattan Project, and deserve to remembered. The name itself, “Manhattan Project,” is commonly thought to […]

Located at 3280 Broadway, the Nash Garage Building was originally an automobile dealership which was purchased by Columbia University and converted into a pilot plant to create the barrier material for Oak Ridge, TN’s K-25 gaseous diffusion plant. While the theory surrounding this process was relatively simple, producing a functional barrier was another matter. The […]

In 1942, General Leslie Groves approved Oak Ridge, Tennessee, as the site for the pilot plutonium plant and the uranium enrichment plant. Manhattan Project engineers had to quickly build a town to accommodate 30,000 workers–as well as build the enormously complex plants. “Site X” By the time President Roosevelt authorized the Manhattan Project on December […]

Philip Abelson conducted research on the liquid thermal diffusion method of isotope separation at the Philadelphia Navy Yard. This process was utilized for the S-50 Plant at Oak Ridge. In September 1944, several workers were injured while trying to fix a clogged tube in the transfer room of the liquid thermal diffusion semi-works at the Philadelphia […]

Princeton University was a hotbed for nuclear physics research during the early twentieth century. Much of the research conducted at Princeton allowed scientists to develop and pursue a path to building the world’s first atomic device. In fact, more than two dozen Princetonians were among the core group of brains at Los Alamos, N.M. In […]

The Purdue University Physics Department operated a cyclotron during the early part of the war, conducting important nuclear research. Many of the scientists working on the project were transferred to Los Alamos to continue work on the Manhattan Project. For more information, see A History of Physics at Purdue: The War Period (1941-1945).

With both the K-25 and Y-12 plants suffering setbacks in the spring of 1944, Oppenheimer urged Groves to approve the construction of a thermal diffusion plant. The U.S. Navy had researched this method for three years and was already building a pilot plant of 100 columns in Philadelphia.  After reviewing Oppenheimer’s suggestions, Groves decided in […]

Santa Fe was the first stop for many scientists, engineers, Women’s Army Corps, military police and all others assigned to work on the top-secret project at Los Alamos.  Lamy Ten miles from Santa Fe, Lamy is the nearest stop on the former Atchinson, Topeka and Santa Fe Railway. Young men and women assigned to work […]

Though not a Manhattan Project location, the island of St. John in the US Virgin Islands played an important role in the life of J. Robert Oppenheimer. Soon after he was stripped of his security clearance in the infamous Atomic Energy Commission hearing, Oppenheimer and his wife Kitty began spending time on the island. They […]

In early 1944, DuPont, the operating contractor at Hanford, foresaw the need for four chemical separation facilities. These facilities, designated the T and U plants at location 200-West and the B and C plants at location 200-East (the C plant was never built), would be located approximately ten miles south of the reactors. The separation […]

Tinian Island was the launching point for the atomic bomb attacks against Hiroshima and Nagasaki, Japan. One of three islands in the Northern Marianas, Tinian is less than forty square miles in size and located approximately 1,500 miles south of Tokyo. The round-trip flight from Tinian to Tokyo took B-29s an average of twelve hours. […]

The birth of nuclear weapons occurred on July 16, 1945 at the Alamogordo Bombing and Gunnery Range in New Mexico, 230 miles south of Los Alamos. Gadget (as the bomb was known) was an implosion plutonium bomb, like the one used at Nagasaki, and detonated with 20 kilotons of force, slightly more than the Little […]

The “Rad Lab” was the short name for the Radiological Laboratory at the University of California, Berkeley. Its director was Nobel laureate Ernest O. Lawrence. He gained recognition for his 60″ cyclotron,  a type of particle accelerator first invented in the early 1930s. Known as “atom smashers,” cyclotrons accelerate atoms through a vaccuum and use electromagnets […]

Small experiments studying the effects of radioactive isotopes, including plutonium, uranium, and polonium, on humans were conducted in the Manhattan Annex of the Strong Memorial Hospital located at the University of Rochester. The purpose of these studies was to examine the safety of small amounts of radiation on those working at other Manhattan Project sites. At […]

Located in a bucolic setting surrounded by tall pines, these humble wooden and asbestos-shingled buildings were where the world’s first atomic device was assembled. Here scientists, engineers, and explosives experts worked around the clock on the “Gadget,” the first plutonium-based atomic explosive.

In a tiny, two-room office located on the fifth floor of the New War Building, General Leslie R. Groves and a handful of staff members oversaw the activities and functions of tens of thousands working on the top-secret Manhattan Project. Groves had selected Washington D.C. as headquarters shortly after being named director of the Project […]

Wendover Air Field was chosen as the rear training base for the 509th Composite Group because of its isolation. It is located in the salt flats located 125 miles west of Salt Lake City. Colonel Paul Tibbets, head of the 509th, remarked upon seeing Wendover for himself: “The end of the world, perfect.” Life at […]

Wilmington, Delaware is the headquarters of E. I. du Pont de Nemours and Company, an American chemical production company that played a significant role in the Manhattan Project and the making of the atomic bomb. The DuPont Company was founded in 1802 in Wilmington, Delaware by Éleuthère Irénée du Pont, a French gunpowder manufacturer. As […]

The X-10 Graphite Reactor was the first reactor built after the successful experimental “Chicago Pile I” at the University of Chicago.  On December 2, 1942, using a lattice of graphite blocks and uranium rods, Enrico Fermi proved that a nuclear chain reaction could be controlled. Scientists knew that it would only be a matter of […]

The Y-12 Plant in Oak Ridge used the electromagnetic separation method, developed by Ernest Lawrence at University of California-Berkeley, to separate uranium isotopes. Electromagnetic Separation The electromagnetic separation method was the most developed of the potential ways to produce fissile material at the start of the Manhattan Project. Ernest O. Lawrence, working at the University […]