Possibility, Opportunity, Capability. A Critical Reinterpretation for Accessibility Planning in the 15-Min City

The application of the 15-min city principles to urban planning cannot be separated from the appropriate design of mobility, walking and bicycling, and its spaces. The ‘right to mobility’ is often lumped together with the simple guarantee of the ‘right to transport’, oversimplifying the complexity of the phenomenon. Freedom of movement affects numerous urban issues such as the possibility of having flexible spaces and activities in proximity areas, the guarantee of better access to territorial resources, and the opportunity to reach as many destinations as possible. All the situations above, and many more, can be linked with the concept of accessibility, an indispensable factor in ensuring the implementation of sustainable, efficient, and equitable mobility systems. In the contribution, the concept of accessibility is split into three components: possibility, opportunity, and capability. Using three Italian case studies and three main definitions of accessibility, the possibility of movement through multimodal transportation at the spatial scale, the opportunity for citizens to have proximity services in the neighborhood, and the ability of urban space to enhance the capabilities of its inhabitants are investigated. The study of the accessibility issue through this taxonomy can help define new readings of the urban phenomenon and, simultaneously, systematize characters and design criteria useful for the 15-min city projects.