Beyond 15 Minutes: A Taxonomy for the City of Proximity

In recent years, the concept of the “15-min city” has gained prominence in international urban planning discourse as a model for enhancing urban livability through improved access to essential services within short distances. However, its rapid diffusion and the absence of a consolidated theoretical framework have led to a wide range of interpretations, resulting in the emergence of the broader and less clearly defined concept of the “X-minute city.” This study aims to move beyond the rhetoric of temporal proximity by developing a critical taxonomy of urban proximity models, based on three key dimensions: time threshold, type of services, and governance model. Through a comparative analysis of 35 case studies, selected from capital cities and high-density urban areas, the research highlights significant differences in the configuration of these models. These variations reflect diverse approaches to managing urban time, service complexity, and decision-making processes. The findings are summarized in a ternary diagram that visualizes the main urban clusters, shedding light on both successful practices and recurring challenges. The study emphasizes the importance of a contextualized and strategic approach to proximity planning—one that can adapt to the specific social, spatial, and institutional characteristics of each territory. This article contributes to the scientific debate by offering a practical tool to distinguish between symbolic applications and real transformations. Ultimately, the future of urban proximity does not lie in strict adherence to a standard time threshold, but in the model’s ability to regenerate the relationship between urban space, citizenship rights, and quality of life.