Migrants represent a structural and dynamic phenomenon. It involves social and urban organization; at the same time, it confirms the strong connection between multi-ethnicity and architecture. Moreover, this phenomenon contributes to redefine city boundaries, not only in its external borders, but also in social distances within urban territory; so, the border change its meaning, redefining itself as a physical and mental barrier. Although migrants are really growing in our cities, the attention to their ways to use housing space is still weak. So, the paper stress the cultural relativism of this issue, through the different meanings that social and cultural areas give to terms like centre, distance and border.