Nuclear power in Brazil has a long and rich history, including complex international trade agreements, technological dominance, military secrets, and a major radiological accident. However, it has received little attention from Brazilian Geography, which could broaden the debate on the subject beyond the traditional technical-economic perspectives. We applied the relational theory of place, the typology of energy landscapes, and the concept of nuclearity to describe the sociospatial transformations that occurred after the establishment of the Nuclear Power Station in Angra dos Reis, as well as the connections of this enterprise with the nuclear fuel cycle. We used mixed methods that include: document analysis; semistructured interviews with experts; analysis of historical series of images, including the application of Remote Sensing and Geoprocessing techniques; and exploratory and confirmatory fieldwork. We presented the initial milestones in the siting of nuclear reactors around the world, to put in context Brazilian studies that led to the selection of Praia de Itaorna, Angra dos Reis (RJ), to receive the first nuclear power plant in the country. This choice made Itaorna a nuclear place. The installation of the Nuclear Power Station in 1970 and its slow and discontinuous expansion over the next five decades led to a series of alterations in the composition of the place and in its degree of nuclearity. During this period, the domain of meaning remained stable, while the domains of nature and social relations had significant changes, indicating landscape transformations. These must be understood within a broader context of socio-spatial transformations in the municipality of Angra dos Reis, which includes the rise (petroleum terminal and Nuclear Power Station) and fall (charcoal forests) of energy landscapes. The Nuclear Power Station became a landmark, modified the coastline, and created an exclusion area that allowed, to a certain extent, the regeneration of the surrounding vegetation. On the other hand, it stimulated the growth of a population center in Mambucaba that reduced the vegetation there. The energy landscape of the Nuclear Power Station is characterized by high energy density, spatial dominance, and temporal permanence. The establishment of the Nuclear Power Station took place simultaneously with the establishment of the Nuclear Fuel Factory (Resende – RJ) and the Planalto de Poços de Caldas Mining Plant (Caldas – MG). These three places are connected through the nuclear fuel cycle and their existence depends on flows of materials (mainly uranium), people and financial resources, which are (or were) established between them. This interdependence differentiates nuclear energy landscapes from others, such as those formed by hydroelectric plants or wind farms. The three nuclear landscapes have high energy density. Among them, the Mining Plant causes the deepest transformation, has greater spatial dominance and temporal permanence, while the Fuel Factory is located at the other extreme. The relational theory of place, the typology of energy landscapes, and the concept of nuclearity proved to be a robust theoretical basis for the study of socio-spatial transformations in the nuclear fuel cycle and constitute promising tools to be applied to energy planning.