Statistical area designating a commuter belt around an urban unit
A periphery, (Fr: couronne) is an INSEE (French demographic statistics institution) statistical area[1] designating a commuter belt around an
urban unit (Fr: unité urbaine). Together these complete the INSEE
urban area statistical area.
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 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.