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Castle of the Week 113 - Olavinlinna Fortress, Finland

Olavinlinna Fortress Olavinlinna Fortress, also known as Olofsborg (Swedish) or Olaf's Castle, is located on a small rocky islet in Lake Saimaa in Savonlinna, Finland. At the time the castle was built, Finland was a part of Sweden, along with Denmark and Norway. Sweden had been engaged in battle against Novgorod (Russia) for some 30 years, when finally a peace treaty was signed. The Peace of Pähkinäsaari (aka Treaty of Nöteborg), signed in 1323, ended the war and regulated the border. The border wasn't fixed, however, and border disputes were common. By the 15th century, the Grand Duchy of Moscow had become increasingly more powerful and more of a threat to the Swedish Crown. Wyborg was the only Swedish border castle at the time, and it was decided that another one was necessary.
A Danish knight, Erik Axelsson Tott, first fortified the nearby town of Viipuri, surrounding it with stone walls, then commenced construction on Olavinlinna in 1475. The castle was named after St. Olaf, the patron saint of knights. The workmen were protected against harassment from the Russians by a series of wooden defenses. The Russians, claiming that the castle was being built on their side of the border (found to be a true claim in more recent years), sought to disrupt the construction in ways such as attacking the supply barges. Erik died in 1481, but his brother continued until the castle was finished in the 1490s. A few further modifications were made in the following centuries. Olavinlinna Fortress
Olavinlinna Fortress Olavinlinna Fortress has a bailey, 3 bastions on one side, and three towers rising above the battlements on the other side. The towers reach 20m high, while the wall connecting them is 10m high. Two of the towers, Bell Tower and Church Tower, still exist today, but the third, St. Eric's Tower, was taken down or destroyed in the early 18th century. Olavinlinna Fortress is an example of a late medieval defensive castle, built for both medieval and gunpowder warfare. The bastions and towers were designed to hold cannons, though they weren't actually added until later. The castle's lake location gave it a huge defensive advantage. It couldn't be reached by tunneling, and it was out of range of medieval war machines. If the lake froze over then the enemy could cross over, but fortunately the water was very fast-moving so that rarely happened. Cannon were the only effective weapons against Olavinlinna Fortress.
Olavinlinna Fortress
In 1495 the Russians besieged the nearby city of Viipuri. After mounting an unsuccessful attack against the castle, the Russians were forced to withdraw after being met in battle by Bishop Pietari Kylliäinen and his force of 150 men. Early the next year the Russians returned and destroyed a relief force sent to defend the castle, then again withdrew. Later that same year of 1496 the Russians again attacked, but remained unsuccessful in their effort to capture the castle.

In 1714, during the Great Northern War, Olavinlinna Fortress surrendered to the Russians following a long siege. It remained in Russian control until the war ended with the signing of the Peace of Uusikaupunki in 1721. Under that treaty Sweden ceded most of its territories on the southern and eastern shores of the Baltic Sea, and Russia withdrew from most of Finland. The castle returned to the Swedes for a time. Then it returned to the Russians as a result of the next treaty, the Peace Treaty of Turku in 1743. This time the Russians kept the castle for around 100 years. In 1809 Finland became an autonomous part of Russia, but Russian troops remained in the castle until 1847.

Olavinlinna Fortress Beginning in 1850 the castle served as a prison for a few years. It sustained damage in the 1860s from two fires. Parts of the castle were restored in the 19th century, then it underwent a full restoration from 1961-1975. Today Olavinlinna Fortress is owned and operated by the Finnish state. It is open to tourists and special events, and hosts the Savonlinn Opera Festival every July.

Photographs courtesy of Castles of the World.
Write-up by Kester*.


*) denotes a former staff member.