Orivirran saarto is a ruin of a 16th-century

fortress A fortification is a military construction or building designed for the defense of territories in warfare, and is also used to establish rule in a region during peacetime. The term is derived from Latin ''fortis'' ("strong") and ''facere'' ...

located in

Savonranta Savonranta is a former municipality of Finland. It became part of Savonlinna in early 2009. It is located in the province of Eastern Finland and is part of the Southern Savonia region. The municipality had a population of 1,263 (2003) and cov ...

Finland Finland ( fi, Suomi ; sv, Finland ), officially the Republic of Finland (; ), is a Nordic country in Northern Europe. It shares land borders with Sweden to the northwest, Norway to the north, and Russia to the east, with the Gulf of B ...

. It is believed to be built some time between 1540 and 1550 and was used until the beginning of the 17th century. Its status was to be an early warning for the

St. Olaf's Castle Olavinlinna (also known as St. Olaf's Castle; sv, Olofsborg; german: Olafsburg; literally ''Olof's Castle'') is a 15th-century three-tower castle located in Savonlinna, Finland. It is built on an island in the Kyrönsalmi strait that connects the ...

which is still located 50 km to south. It has a four cornered layout with dimensions of 60 m by 20 m build from stones and an outer fortress around 65 m by 75 m. When operational it had 300 to 400 soldiers and 5 to 10

cannon A cannon is a large- caliber gun classified as a type of artillery, which usually launches a projectile using explosive chemical propellant. Gunpowder ("black powder") was the primary propellant before the invention of smokeless powder ...

s. In 1592

Russia Russia (, , ), or the Russian Federation, is a List of transcontinental countries, transcontinental country spanning Eastern Europe and North Asia, Northern Asia. It is the List of countries and dependencies by area, largest country in the ...

ns and

Cossack The Cossacks , es, cosaco , et, Kasakad, cazacii , fi, Kasakat, cazacii , french: cosaques , hu, kozákok, cazacii , it, cosacchi , orv, коза́ки, pl, Kozacy , pt, cossacos , ro, cazaci , russian: казаки́ or ...

s destroyed the fortress. It did not survive after that and today there exists only some ruins of the fortress with a memorial stone (1965, H. Havas).

Sources

*https://web.archive.org/web/20070821230521/http://www.savonranta.fi/orivirta.html and *"Vanhan Kerimäen historia", in Finnish, , and "Savonrannan kunnan historia", Former buildings and structures in Finland Forts in Finland Buildings and structures in South Savo Buildings and structures demolished in the 16th century {{Finland-struct-stub