The Kastelli Giant's Church is a ruin in the Finnish region of Pohjois-Pohjanmaa. It is a rectangular stone enclosure measuring 60 by 35 meters. The wall is 2 meters high and 7 meters wide and there are 6 entrances. The fence is surrounded by 20 heaps of stones. It was discovered during excavations in 1920.
The construction was made about 2700-2200 BCE at the time of the subneolithic ceramics culture and may have served as a storage place for food, including killed seals. At that time, this place was about 45-55 meters lower than it is now, and probably on a small island on the coast. Today, this place is 57 meters above sea level, due to the post-glacial soil rise.