Oulu Castle

Oulu Castle is a medieval fortification in Oulu, with a cellar and rampart section remaining on Linnansaari island in the river delta. The site includes an exhibition space in the cellar and a café housed in an 1875 observatory tower that visitors can access.

Swedish forces built the castle in 1590 as a strategic position against Russian expansion, starting with wooden and earthen structures. A lightning strike in 1793 destroyed the gunpowder magazine and brought about major damage to the original fortification.

The cellar exhibition shows how Oulu grew and changed through different periods of settlement and trade. Visitors can see objects and information that tell the story of what life was like in this river delta location across the centuries.

The castle grounds and cellar can be explored during the opening hours of Tähtitorni Café, which operates from the 1875 observatory tower. Wear sturdy shoes as the site is on an island and the terrain can be uneven.

A lightning strike in 1793 destroyed the gunpowder magazine in a catastrophic explosion that permanently damaged the medieval structure. This dramatic event essentially ended the castle's use as an active fortification.