Old-New studies on city limits and fringe-belts. Expanding-shrinking urban events. Brief notes on the internal and external frontiers in Chinese and African cities and on a new European limes on the Mediterranean Sea

Ever-growing urban form and the limits of fringe-belt theories. This paper presents comparative insights on city limits and fringe belts studies, considering the impact of historical and economic events – as migrations and ethnic groups coexistence – on urban typo-morphologies both as recent global issues and as historical retrospect conditions of urban life. In this framework ‘internal’ and ‘external’ urban boundaries emerge as concepts somehow related to city limits and fringe-belts studies that deserve a new agenda and additional research competences and supplying methodologies. Therefore, this study intends also to give evidence to the limitations of the traditional theories on urban form and fringe-belts if applied to contemporary urban events.