Abstract
The border between Lille and the Belgian border is seen as very open and around 200 000 people are living in the Belgian part of Lille conurbation. Yet it is perpetuated. This study serves a dual purpose: first, the development of a cultural border system operating here specifically in the field of recreation and consumption. This then makes it possible to propose a tool for analyzing territorialized identities that are built around the border. Through the historically and therefore ideologically dated evolutions of the practices of the frontier, one sees in fact the permanent need to introduce a break, an instrumented discontinuity in the service of the construction of the identities of the individuals who thus fit in groups but also identities of the groups themselves. To be attractive these groups must present themselves as precise socio-spatial entities and thus well delimited populations.