Oulu (ōˈlō) [key], Swed. Uleåborg, city (1998 pop. 115,493), capital of Oulu prov., W central Finland, at the mouth of the Oulu River on the Gulf of Bothnia. It is a seaport and has metal shops, leather plants, and wood-processing and other industries. The city grew around a castle founded in 1590, was chartered in 1610, and became (19th cent.) an important commercial center. It was destroyed by fire in 1882 and rebuilt. The Univ. of Oulu was founded in 1959. It is also the site, since 1889, of the world's oldest cross-country ski race.