The basic idea underlying this research is that urban planning is one of the main causes of environmental degradation. Despite its relevance in impacting ecosystems, the current methodological assessments across Europe still fail to include spatial planning as a relevant factor. This paper aims to formulate an innovative methodology for the evaluation of ecosystems for protecting land at risk of degradation. This methodology is exemplified by the case of Spanish spatial planning applied in the Community of Madrid, being also capable to be employed in other European State Members after a cartographic adaptation. The proposed methodology specifically implements a European approach to the scale of regional and local spatial planning based on the “Mapping and Assessment of Ecosystems and their Services” (MAES) project. Among the main results, four outcomes stand out. The first is the novelty to provide a methodology capable of dealing with natural values at regional and municipal levels based on a spatial-planning-based scale (1:20,000). The second result regards the incorporation of new attributes tied to existing ecosystems during the drafting of spatial plans, thus improving the quality of the information to make better decisions in terms of environmental protection. The third result is the more accurate environment assessment due to the inclusion of a new element of direct pressure on ecosystems, while the fourth outcome is that the proposed methodology detects the impacts of the drivers of change in the Community of Madrid. Although the cartographic information is defined at the regional scale, the results obtained can be linked to the municipal planning scale. The proposed methodology can be a much more useful tool for regional spatial planning for three main reasons: it works at the same scale as regional planning (1:20,000), it incorporates the environmental information necessary for the correct identification of natural values and impacts at the municipal level, and it works with geographic information systems. These reasons allow an easier and quicker incorporation of ecosystems in spatial planning tools by simultaneously interpreting and comparing different land protection issues such as ecosystem loss and ecosystem services.

Cities consume over 75% of natural resources, produce over 50% of global waste, and emit 60–80% of greenhouse gases. The scenario that by 2050 two thirds of the world population will live in cities, highlights how cities are still responsible for the growing consumption characterized by linear economic processes, with the production of various types of waste. In this unsustainable framework, the Circular Economy offers the opportunity to shape the urban system by means of rethinking the possibility to produce and use goods and services, exploring new ways to ensure long-term prosperity. The Circular City paradigm contains in fact all the principles of the Circular Economy: recovery, recycling, and sharing. In particular, Circular City also introduces actions related to the development of renewable energy communities, use of green materials, CO₂ absorption approaches, and Proximity Cities. This work aims to develop a methodology to build a composite index (Circular City Index) capable of measuring the degree of implementation of urban policies that may enable an ecological transition of public assets. Circular City Index was applied to the military cluster of the city of Cagliari (Sardinia, Italy), a significant case study to guide circular policies in public properties for civil and military uses.

Accessibility and urban walkability are the cornerstones of urban policies for the contemporary city, which needs to be oriented towards sustainable development principles and models. Such aims are included in the objectives of the 2030 Agenda, as well as in the ambitious objectives of the ‘European Green Deal’. These concepts are closely linked to the paradigm of a sustainable city—livable, healthy and inclusive—based on a system of high-quality public spaces and on a network of services and infrastructures, both tangible and intangible, capable of strengthening and building new social, economic and environmental relationships. It is necessary to recognize potential opportunities for connection and permeability in consolidated urban environments. These are very often fragmented and are characterized by enclaves of very different kinds. Ghettoes and gated communities, old industrial plants and military installations and facilities, to cite a few, represent examples of cases where closures on urban fabrics are realized, impeding full walkability and accessibility. Within such a framework, the present research is aimed at focusing on a particular set of enclaves, such as those represented by the military sites being reconfigured to civilian use, a phenomenon that characterizes many urban areas in the world; in Europe; and in Italy, in particular, given the recent history and the Cold War infrastructure heritage. In such a sense, the city of Cagliari (Sardinia Island, Italy) represents an interesting case study as it is characterized by the presence of a series of military complexes; real ‘enclaves’ influencing the proximity connections; and, more generally, walkability. Building on previous research and analysis of policies and projects aimed at reintroducing, even partially, this military asset into civilian life (Green Barracks Project (GBP)-2019), this paper proposes and applies a methodology to evaluate the effects of urban regeneration on walkability in a flexible network logic, oriented to the ‘15 min city’ model or, more generally, to the renewed, inclusive, safe “city of proximity”, resilient and sustainable.