​PETROZAVODSK, a town and episcopal see of Russia, capital of the government of Olonets, on the west shore of Lake Onega, 190 m. N.E. of St Petersburg. Pop (1865), 11,027, (1897), 12,521. Two cathedrals, built towards the end of the 18th century, a mining school, an ecclesiastical seminary and a government cannon-foundry are the Chief public buildings and institutions. Peter the Great founded ironworks here in 1703, but they continued in operation only twenty-four years The cannon-foundry was instituted in 1774. Petrozavodsk became the capital of the government of Olonets in 1802.