The goal of the Masterplan was to accommodate a population of 270,000 inhabitants in an area of 1,140 hectares, located in São João da Barra, RJ, to support the future Port, Logistics, and Industrial Complex of Porto do Açu, which by 2026 will include, in addition to the port, a shipyard, steel mills, a thermal power plant, and a large industrial district. The conception of "Cidade X" was based on pre-existing physical and environmental conditions, with the central idea being a complex of lagoons and canals that will serve multiple functions, such as enabling a new implementation level, creating a drainage control system, providing quality public spaces, and enabling the implementation of waterway transport. The entire project was structured with environmental and urban sustainability guidelines, addressing mobility, compact neighborhoods, pedestrian priority, alternative transportation, diversity, and accessibility.