//
Photo: Henkkapet, CC BY-SA 4.0 via Wikimedia Commons
The castle was damaged by attack in the 18th century and finally blown to pieces in 1793 when lightning struck the gunpowder magazine. What you see now is the maritime observatory built on the ruins; it's set in a pleasant park, and you can climb the tower for views. There's a café (Tähtitornin kahvila) within. The cellar (same hours) displays info on the castle - mostly in Finnish, but there's more in the Northern Ostrobothnia Museum.
© OpenStreetMap contributors
A "water park" meaning a floated obstacle course in the Oulu river delta. Right next to the Oulu castle ruins and cafe, so you can get a coffee or a cold beer after!
Raatin uimahalli
Public pool and gym. Renovated in 2010. The closest public pool to downtown. Pools include children's pool, teaching pool, two 25 meter pools and a cold-water pool.
Pohjois-Pohjanmaan Museo
Closed for renovation until 2026A great museum on the history of Northern Ostrobothnia, especially the history of Oulu. Exhibitions on four floors.
Oulun Kaupunginteatteri
Plays in Finnish.
Merimiehenkotimuseo
The Sailor’s Home Museum is on the idyllic island of Pikisaari near downtown Oulu. The museum is in the oldest surviving wooden building in Oulu, also known as Matila House, and is the former home of sailor Isak Matilainen.
Oulun tuomiokirkko
Neoclassical Lutheran cathedral built in 1832 after its predecessor burned down. The architect Carl Ludvig Engel also designed the buildings of Senate Square in Helsinki.