Reviewed by: Camp Century: The Untold Story of America's Secret Arctic Military Base under the Greenland Ice by Kristian H. Nielsen and Henry Nielsen Antoine Bousquet (bio) Camp Century: The Untold Story of America's Secret Arctic Military Base under the Greenland Ice By Kristian H. Nielsen and Henry Nielsen. New York: Columbia University Press, 2021. Pp. 352. This recent translation of a 2017 research monograph by two Danish historians of science brings to the attention of English readers a well-publicized but now largely forgotten episode of the Cold War involving the construction of a U.S. Army base under the Greenland ice. Camp Century operated between 1959 and 1967 in the northwestern area of the Arctic territory, 150 miles (240 kilometers) from the still active U.S. Air Force base in Thule. Stretching across 6,000 feet (1,800 meters) of tunnels, Camp Century was home to up to 200 scientific and military personnel and powered by a portable nuclear reactor. Officially, the camp's purpose was to trial construction techniques in the Arctic environment and support scientific experiments. Its ulterior motive, concealed to its Danish hosts and only revealed in 1995, was in fact to prepare the ground for Project Iceworm, a planned network of 600 nuclear missiles hidden under the ice sheet. Camp Century delivers a fascinating and richly documented overview of the site's history and enduring influence. Across nine chapters, the book covers the sensitive political negotiations between the governments of the United States and Denmark, their careful management and vigilant oversight of any media coverage, the details of the camp's construction and everyday operations, the military R&D and scientific research conducted there, its eventual abandonment and more recent rediscovery. The text makes for a highly accessible and engaging read, a testament to the skills of both authors and translator. The writing is supplemented by abundant photographs and illustrations, bringing to life the history of the camp and helping to visualize the considerable accomplishments it entailed. Two dominant themes permeate the narrative. The first is the delicate political balance necessary to accommodate American military presence on Denmark's sovereign territory. For the Danish government, living up to its NATO commitments without arousing public disquiet at home was akin to walking a very narrow tightrope. Accordingly, media reporting on both sides of the Atlantic was closely monitored to prevent anything deemed too sensitive from slipping by. In all this, the cooperation between the two governments wholly bypassed the local Greenlandic authorities and population, [End Page 1234] whose views never entered into consideration. Only in the last few decades has their voice become more audible, notably regarding the clean-up cost of past American military activities, yet still only with limited purchase on the terms of the underlying Defense Agreement binding the United States and Denmark since 1951. The second theme concerns the battle pitting the American military's determination to impose itself on the Arctic geography against the environmental resistances encountered there. In the Pentagon's mind, Greenland was quite simply "the world's largest island and stationary aircraft carrier" (p. 176), its unforgiving climate an impediment to be overcome in the erection of a nuclear bulwark against the Soviet Union. The book certainly provides an engrossing account of the feats of ingenuity deployed to solve the engineering challenges met in durably installing human presence in one of the most hostile environments on the planet. The authors also underline the significance of the ice samples collected by the base's scientists in the development of contemporary climate science. The American decision to ultimately abandon Project Iceworm brings these two strands together, since it was primarily motivated by dual concerns over a refusal by the Danish government and the persistent challenges presented by the frozen environment. Indeed, the ice's ceaseless movement resulted in tunnel deformation and collapse over time, requiring continuous maintenance at great cost. The Arctic would thus have the last word, swallowing up the camp following its abandonment in 1967, its remnants progressively crushed by the shifting ice. As Nielsen and Nielsen narrate in the final chapter, concern has recently grown over the environmental hazard posed by the untreated sewage...