Oulu (; ) is a city and municipality of inhabitants in the region of Northern Ostrobothnia, Finland. It is the most populous city in Northern Finland and the fifth most populous city in the country. There are no larger cities (outside of Russia) that are more northerly than Oulu which is also considered one of Europe's "living labs", where residents experiment with new technology (such as NFC tags and ubi-screens) at a community-wide scale.