Planning Accessible Urban Green Infrastructure for Healthy and Fair Historical Towns: The Study Case of Viterbo, Central Italy

Abstract

Urban Green Space (GS) provide fundamental functions for socio-ecological urban systems. GS help to maintain the physical and mental health of citizens, facilitating communication, sport and physical activities and the contact with Nature. Moreover, they are primary reserve for biodiversity in cities and support several regulating (e.g. water cycle, climate mitigation) and cultural ecosystem services. Recently, COVID-19 pandemic has highlighted the beneficial role of GS for citizens. A key aspect for GS effectiveness is its accessibility for city residents. Full accessible GS are public spaces available for all to use free of charge and without time restrictions. Anyway, the accessibility varies for different GS (e.g. private or public) and for different people movement capabilities (e.g. elderly or young). Thus, planning the spatial distribution of different GS is more and more fundamental for the definition of sustainable, resilient, safe and fair urban systems. In this work, a GIS-based accessibility assessment of GS is presented for the city of Viterbo, central Italy. A score of accessibility by different users of GS (total residents, children, elderly people) is calculated on the road network and some planning considerations are presented. The study case is exemplificative for historical town having limited open spaces within the ancient city wall and relevant pressure factors acting on it.