Something strange happened in the US state of Tennessee in 1943. Thousands of young workers poured into a 59,000-acre site about 25 miles west of Knoxville. Vast quantities of materials followed, never to re-emerge. Houses and other facilities were built with record speed. Yet officially Oak Ridge did not exist during the war and could not be found on any map.

What was going on there? Very few people knew at the time, even among the residents. The answer was that this was the starting block in a race against Adolf Hitler to build the atom bomb.



Oak Ridge was one of three “secret cities” of the Manhattan Project, along with Los Alamos in New Mexico and Hanford/Richland in Washington state.

Clockwise from top: The control room of the K-25 plant, Oak Ridge, 1945; the K-25 plant itself; Hanford Construction Camp, Washington. Photographs: National Archives and Records Administration/US Department of Energy, Hanford Collection

More than 125,000 scientists, technicians and support staff occupied the three cities by the end of the war. There is a photo of a Santa Claus being frisked at the gates of Oak Ridge and a local newsletter stamped “restricted”. Anyone aged 12 or over had to wear an ID badge. The use of words such as “atomic” or “uranium” was taboo lest it tip off the enemy.

Yet some social aspects were all too familiar: even these planned communities, which tried to offer residents an idyllic lifestyle and would influence postwar urban construction and design in America, replicated the racial segregation of the era.

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“At first glance they seem like very normal American communities,” says Martin Moeller, senior curator of the Secret Cities: The Architecture and Planning of the Manhattan Project exhibition, which opens on Thursday at the National Building Museum in Washington. “But then before long you start to see things that are strange in a variety of ways, sometimes humorous.”

He offers examples: “Driving by the main hotel in Oak Ridge and seeing that the bar and lounge there is called the reactor room. Starting to see these nuclear symbols on seemingly random buildings around the place but also coming to understand that these were not just typical communities that grew up in a haphazard fashion, that there was a hand of design there even at the beginning of their existence.”

A culture of secrecy prevailed, with strict security measures in place. Photograph: Courtesy of the US Department of Energy and the Oak Ridge Public Library

It was late 1942, less than a year after the US had entered the second world war, when the US Army Corps of Engineers quietly began acquiring vast tracts of land in remote areas of three states. The few residents of these areas were summarily evicted and their houses demolished.



Soon thousands of young workers arrived from far and wide, initially occupying tents and other makeshift shelters within the newly designated military reservations. Shielded from public view by natural barriers and security fences, the workers quickly erected hundreds of buildings, ranging from prefabricated houses to industrial structures of unprecedented scale.

The goal was singular. Aware that the Nazis were pursuing nuclear weapons – though they were not as far along as thought at the time – the US would invest unfathomable money and manpower to get there first. The cause could scarcely have been more urgent.

“Despite that, in building these communities, it was considered important to create housing in environments that were comfortable for the people who would be working for the scientists and engineers who would be doing this important work,” explains Moeller, who first visited Oak Ridge three decades ago when his future father-in-law was a nuclear physicist with the national laboratory there.

Housing at Oak Ridge. Clockwise from top: a government-issue trailer decorated with trellis, 1944; postwar housing designed by Skidmore, Owings & Merrill, 1948; a “Flat Top” prefabricated house, 1944. Photographs: National Archives and Records Administration/SOM © Torkel Korling



“There was agreement that they needed to feel at home. They needed to have a community that felt ‘normal’. And so during this time of national emergency, the US government built single family houses in what we would now consider typical suburban neighborhoods, instead of just jamming all of these people into dormitories and barracks as I would think almost any other country in the world would have done for time. That to me, in of itself, is extraordinary.”



He adds: “These cities really were proving grounds for emerging ideas about town planning architecture and construction. In many cases they were continuing movements that were already in existence.”



Built from scratch in half a year to produce fuel for atomic bombs, Oak Ridge was initially conceived as a town for 13,000 people but grew to 75,000 by the end of the war, the biggest of the secret cities. The housing was designed by Skidmore, Owings & Merrill (SOM), now one of the biggest and most influential architecture firms in the world. And yet while Oak Ridge seemed to exist in a bubble, it was also very much of its time.



The “Rhythm Engineers” residents’ musical group on stage, Oak Ridge, 1945; the mess hall of Hanford Construction Camp, circa 1943-45. Photographs: National Archives and Records Administration

Moeller continues: “Although these cities were very much conceived as forward-looking communities – they really wanted places that were idyllic in many ways, great places to raise families – nonetheless segregation was designed in from the start. It was just considered to be a given by all parties concerned. There were racial issues that were baked into these communities.”

Although these cities were very much conceived as forward-looking communities, segregation was designed in from the start Martin Moeller, Secret Cities curator

SOM’s initial plan called for a “negro village” at the eastern end of town, furthest from the work sites, which was to include housing similar to that provided for white residents. But as Oak Ridge grew quicker than expected, those plans were abandoned and most African American residents were relegated to “hutments”: rudimentary plywood structures barely superior to tents.

They were frigid in the winter – heated with crude stoves – and sweltering in the summer and offered little privacy. They lacked internal plumbing so residents had to use collective toilet facilities. Even married couples were not allowed to live together in the hutment camps. And residents were routinely subjected to more surveillance from the security authorities than those living in the more permanent neighbourhoods.

By the end of the war, most of the white families had been moved out of the hutments and, as the population was then shrinking, went into more permanent housing. But many of the African American families continued to live in the basic dwellings until the early 1950s.

Most African American residents were relegated to “hutments”: rudimentary plywood structures. Photograph: Edward Westcott/National Archives and Records Administration

There would be a twist, however. Moeller says: “In the postwar period, Oak Ridge, having now been settled as a place full of academics and very well-educated people otherwise, was one of the leaders in the desegregation movement in the south. In fact, two of the first public schools in the south to be desegregated were in Oak Ridge. Oak Ridge even threatened to secede from Tennessee in order to desegregate. So there was a relatively quick turnaround.”

The night that the news broke that the bombs had been dropped ... I sat in my dorm room and cried. Mary Lowe Michel, Oak Ridge typist

When the US dropped the atom bomb on Hiroshima, Japan, in 1945, killing tens of thousands of people to force an end to the war, the city’s secret was out. Many residents celebrated. One local newspaper declared: “Atomic super-bomb, made at Oak Ridge, strikes Japan.” Another said: “Oak Ridge Attacks Japanese ... Workers thrill as atomic bomb secret breaks; press and radio stories describe ‘fantastically powerful’ weapon; expected to save many lives.”

Not everyone was jubilant, however. Mary Lowe Michel, a typist in Oak Ridge, is quoted in the exhibition as saying: “The night that the news broke that the bombs had been dropped, there was [sic] joyous occasions in the streets, hugging and kissing and dancing and live music and singing that went on for hours and hours. But it bothered me to know that I, in my very small way, had participated in such a thing, and I sat in my dorm room and cried.”

All three cities remained part of the military industrial complex, continuing to work on nuclear weapons during the cold war as well as broader scientific research; today Oak Ridge is heavily involved in renewable energy. The unique subcultures that grew during their early years of isolation also survive.

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Moeller observes: “These people really in many ways had to commit to create their own culture and interestingly, even to this day, some of the little theatre companies and musical troupes that were formed during world war two still exist and still operate as community cultural organisations in theses cities.”

That includes “atomic culture”, or, to put it another way, gallows humour. At one of the most popular lunch spots in Oak Ridge, there are pictures of mushroom clouds on the wall. The logo of Richland high school contains a mushroom cloud. “There are pictures of atomic symbols and so on and I hasten to point out that that’s not because the residents of these communities are callous.

“They realise the seriousness of the work that was done in those places during the war and afterwards during the cold war. But it’s kind of like doctors’ humour in emergency rooms. They’re somewhat notorious for being irreverent in their humor about medical conditions. It’s how they deal with the seriousness of what they do.”

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