A periphery, (''Fr: couronne'') is an INSEE (French demographic statistics institution) statistical area
/ref> designating a commuter belt around an urban unit
In France, an urban unit () is a statistical area defined by INSEE, the French national statistics office, for the measurement of contiguously built-up areas. According to the INSEE definition , an "unité urbaine" is a commune alone or a grou ...
(''Fr: unité urbaine''). Together these complete the INSEE urban area
An urban area is a human settlement with a high population density and an infrastructure of built environment. Urban areas originate through urbanization, and researchers categorize them as cities, towns, conurbations or suburbs. In urbani ...
statistical area.
Based on France's '' commune'' system (interlocking administrative subdivisions often comparable to civil parish
In England, a civil parish is a type of administrative parish used for local government. It is a territorial designation which is the lowest tier of local government. Civil parishes can trace their origin to the ancient system of parishes, w ...
es, town
A town is a type of a human settlement, generally larger than a village but smaller than a city.
The criteria for distinguishing a town vary globally, often depending on factors such as population size, economic character, administrative stat ...
s or cities
A city is a human settlement of a substantial size. The term "city" has different meanings around the world and in some places the settlement can be very small. Even where the term is limited to larger settlements, there is no universally agree ...
), a commune is considered part of a couronne when
# it is not densely constructed enough or is too isolated to be part of any '' unité urbaine'' (or "'' pôle urbain''" if it is the core of the agglomeration), and
# at least 40% of its population commutes to workplaces in a '' unité urbaine'' or '' pôle urbain'', or to another commune connected to a '' unité urbaine'' through the same criteria.
References
Demographics of France
Subdivisions of France
INSEE concepts
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