Cities under pressure: Tourism intensity and the erosion of social capital in Italy

This research note reconceptualizes tourism intensity as a structural stressor capable of undermining the social capital that sustains urban life. Drawing on a 15-year longitudinal panel data of 42 Italian cities (2009-2023) and employing a dynamic System GMM estimator, our study analyses how varying levels of tourism intensity affect social capital, operationalized through a multi-indicator civic engagement index. The results reveal a non-linear erosion process, where social capital remains stable at low and moderate levels of tourism intensity but declines sharply once cities surpass high-intensity thresholds. Our findings provide a quantifiable basis for understanding overtourism as a threshold-based social phenomenon, extending beyond resident perceptions to the structural weakening of civic cooperation, trust, and engagement. The present study advances theoretical debates by positioning tourism intensity as a civic destabilizer and highlights the need for governance models that protect social capital as a critical urban asset. Without such safeguards, cities risk transitioning from vibrant, participatory communities into socially depleted Non-places.