Why it belongs here
Kostopil (Ukrainian: Костопіль [kosˈtɔpilʲ] ; Polish: Kostopol) is a small city on the Zamchysko river in Rivne Oblast, western Ukraine (historical Volhynia). It was the administrative center of the Kostopil Raion up to 2020, but is now within the Rivne Raion.
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