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Petrozavodsky Uyezd (Russian: Петрозаводский уезд) was one of the seven subdivisions of the Olonets Governorate of the Russian Empire. Its capital was Petrozavodsk. Petrozavodsky Uyezd was located in the central part of the governorate (mostly in the southern part of the present-day Republic of Karelia, with one part in the northeastern corner of Leningrad Oblast).