Couronne périurbaine

A couronne périurbaine, a statistical area devised by the French INSEE demographic statistics institution, describes a commuter belt area around an area of dense habitation (or unité urbaine to use the same institution's terminology).

Based on France's commune system (interlocking administrative subdivisions often comparable to civil parishes, towns or cities), a commune is considered part of a couronne périurbaine when

1. 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
2. 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.