People make places urban

What makes a place ‘urban’? Here we develop the conceptual case for a simple geo-demographic approach to defining and measuring ‘urbanness’. Through a critical engagement with classic treatises on cities and urbanism, we argue that urbanness is a function of population concentration, which generates the essentially urban experience of living surrounded by strangers and stimulates the social phenomena and environmental modifications traditionally associated with urbanism. We make a clear distinction between urbanness and ‘development’, introduce the concept of ‘ephemeral urbanism’ and propose the development of new continuous indicators of urbanness based on population proximity to complement fixed residential density measures.