Higher immigration and lower land take rates are driving a new densification wave in European cities

Spatio-temporal density trends are considered key indicators of urban development. However, similar density trends may hide different drivers. This study investigates the density trends of 331 European cities between 2006 and 2018 and the underlying trends in residential area and population, broken down into natural change and net migration. The analysis captured a shift in the predominant trend from de-densification (2006–2012) to densification (2012–2018). Two main drivers determined the shift: (i) a more diffused growth of urban population, and (ii) a slowdown of land take for residential use after the global financial crisis of 2008. A clear acceleration in net migration rates, with immigration pushing population growth, occurred in most cities turning from de-densification to densification. Despite path dependencies and enduring differences across regions and city sizes, the distribution of these trends partly redesigned the traditional European East-West dichotomy into a novel center-periphery division.