Source: Building, Construction & Design Network | David Malone | March 7, 2018

The exhibit will run through March 3, 2019.

Aerial view of the K-25 plant, Oak Ridge, ca. 1945.

The K-25 plant was built for the enrichment of uranium through gaseous diffusion, in which gaseous U-235 was separated from U-238 through an incredibly fine mesh. When completed, K-25 was the largest building in the world under one roof. National Archives and Records Administration.

Secret Cities: The Architecture and Planning of the Manhattan Project is a new exhibition at the National Building Museum that explores the highly classified effort to produce the atomic bomb. The exhibit places an emphasis on showcasing the three new “secret cities” that were built to accommodate the tens of thousands of people who worked on the project.

Oak Ridge, Tenn., Hanford/Richland, Wash., and Los Alamos, N.M., will be explored through original documents, photos, artifacts, maps, and models. The three cities were built from scratch by the U.S. government to accommodate the vast number of people and large-scale, secure facilities necessary for the project.

The cities, which were built in about three years, were heavily reliant on prefabricated construction and helped test and develop emerging ideas about planning and design.

The exhibition also touches on the postwar development of the cities, which remain centers of scientific research today. For more information, click here.


“Flat Top” house, Oak Ridge, 1944. During World War II, the U.S. military erected thousands of prefabricated or semi-prefabricated houses across the country. One of the most common houses in Oak Ridge was the B-1 model, commonly known as the Flat Top. Each of these houses was built in a factory and transported by truck in two or three pieces to the site, where it was assembled atop a foundation. The architectural firm of Skidmore, Owings & Merrill (SOM) oversaw the planning of the city and the design and construction of most buildings within it. National Archives and Records Administration.




Control Room at the K-25 plant, Oak Ridge, 1945. Sophisticated equipment was used to monitor and control the potentially hazardous industrial processes at the K-25 plant and other Manhattan Project facilities. National Archives and Records Administration.