Olavinlinna is a 15th-century three-tower castle located in Savonlinna, Finland. It is built on an island in the Kyrönsalmi strait that connects the lakes Haukivesi and Pihlajavesi. It is the northernmost medieval stone fortress still standing. The castle forms a spectacular stage for the Savonlinna Opera Festival, which was held for the first time in the summer of 1912.

The Treaty of Nöteborg, also known as the Treaty of Oreshek, is a conventional name for the peace treaty signed at Oreshek on 12 August 1323. It was the first settlement between Sweden and the Novgorod Republic regulating their border mostly in the area that is also known as Finland today. Three years later, Novgorod signed the Treaty of Novgorod with the Norwegians.