Sociological theories noticed the mutation of the city from first to second mo-dernity. This passage weakened Wirth’s ecological variables (1938) introducing new forms of urbanism. With the urban diffusion’s process and with the dispersion of city’s boundaries, a growing ambivalence has emerged in the new city, the so called "post-metropolis" as a place of belonging and, at the same time, of segrega-tion. The new metropolis is a fluid and complex social space containing processes of aggregation and social disintegration. In this context, ethnic boundaries can be viewed as urban symbols of the second modernity (Sassen 1994). The intention of this essay, starting from a research project on the Eastern quadrant of Rome (Cipollini, Truglia, 2015), extended to the analysis, currently in progress, on the South quadrant, is to carry out an exploration of the metropolitan boundaries of Rome, with a focus on the residential settlement of foreign populations, detecting spatially-continuous ethnic territories or enclaves bounded by margins and sym-bolic boundaries.
Keywords: Ethnic boundaries; symbolic segregations; city; urbanism; foreigner; Rome; community; segregation; sociology.