🏰Olafsborg #Finland🇫🇮

🔶Olafsborg is a 15th—century fortress on a tiny island in the Finnish city of Savonlinna. This is the northernmost medieval fortress that has survived to this day. 

🔶Originally it belonged to Sweden, then it became part of the Grand Duchy of Finland as part of the Russian Empire, and then became part of independent Finland.

🔶The place, a rocky island on Lake Saimaa, was chosen for strategic reasons: firstly, high steep walls run almost along the very edge of the island, and it is difficult to approach them, and it is almost impossible to approach them without being noticed. 

🔶Secondly, the current is very strong, and the water does not freeze even in winter, so it is much easier to defend yourself in severe weather conditions
https://earth.google.com/web/search/Olafsborg