Olsztyn Castle is set on a dramatically bumpy hill among limestone rocks, overlooking Łyna River in northeastern Poland. The castle was built sometime before 1306. It was expanded by Casimir the Great between 1349-59 to defend against the Czechs. Olsztyn later gained a military garrison and was renovated in the Renaissance style in the 16th century.

At that point, it was built on three levels with drawbridge entrances and a moat. In the following years, however, the Hapsburgs and then the Swedes caused significant damage, and the castle fell out of use. Today, visitors can still see the original gothic tower and explore the ingenious manner in which the built elements integrate the area’s rocks and karst caves.