The construction of Olavinlinna castle was begun in 1475 by Erik Axelsson (Tott), and by 1483 the castle was at least partly complete. It withstood the attacks of Russian troops in 1496-96 and passed without conflict into the control of Gustavus Vasa in 1523. The castle underwent repairs in the 16th and 17th centuries, but was taken over by the Russians in 1743. Olavinlinna underwent refurbishment throughout the 18th century and Swedish attempts to recapture it failed.
The military use of the castle ended in 1847, and the first restoration works were undertaken in 1872-78. (Kari Uotila)
The main castle rose on the highest side of the islet, the western side. The main castle consisted of three towers with encircling wall between them. After the main castle was finished, the building of the bailey was started. The bailey had two towers, and the building work was finished at the end of the15th century. At that time the castle with five towers rising on an islet represented the most modern defence architecture with round towers and high encircling walls. (Kari Uotila)
1. Standing main castle and outer bailey. Included store- and living rooms, hall, chapel. Two towers left in main castle and two in outer bailey. (Kari Uotila)
Restoration in the castle occurred in late 19th century as well as in the 20th century. However, the latest large-scale restoration began in 1961 and was finished in 1975, just in time for the castle's 500 -jubilee. After this only small annual repairs have been necessary. (Kari Uotila)