The Lutheran Cathedral of Oulu, completed in 1832 in a restrained Empire style by C. L. Engel — the German-born architect who shaped much of central Helsinki. The current building replaced an earlier wooden church destroyed in the Oulu fire of 1822.
Inside, a portrait of the 17th-century priest Johannes Messenius is the oldest surviving Finnish painting. The cathedral park around it has benches and is one of the prettiest small green spaces in the centre.