The K.H. Renlund Museum is the main local history museum of Kokkola, covering the city's history from prehistoric times through its peak as a maritime trading port to the present. The museum takes its name from a wealthy 19th-century merchant who donated his collections to the city, and the core of the collection reflects the tastes and travels of a prosperous Nordic merchant family of that era.
The maritime collection is particularly strong, documenting Kokkola's role as one of the most important tar-exporting ports in the world during the 18th century. The city's tar trade made it wealthy; the museum explains how tar, cut from the forests of the Finnish interior and floated downriver to the coast, was essential to maintaining the wooden warships and merchant vessels of northern Europe. There are also sections on the Swedish period, the cultural duality of the city's Finnish and Swedish-speaking communities, and the development of the region in the 20th century.