An administrative center is the seat of regional or local administration, or a county city, or the place where the central administration of a municipality is located.
In Russia, the term is applied to the inhabited localities that serve as the seat of government of the entities of the different levels. The only exception to this rule are the republics, for which the term "capital" is used to refer to the seat of government. The capital of Russia is also an entity to which the term "administrative center" does not apply. A similar provision exists in Ukraine.
In the United Kingdom it is the center of a local authority, in what a historic county differs from a county town.
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