The Ostrobothnian Plain or Pohjanmaa is a large lowland in

Finland Finland, officially the Republic of Finland, is a Nordic country in Northern Europe. It borders Sweden to the northwest, Norway to the north, and Russia to the east, with the Gulf of Bothnia to the west and the Gulf of Finland to the south, ...

along the

Bothnian Sea The Bothnian Sea (; ) links the Bothnian Bay (also called the Bay of Bothnia) with the Baltic Sea, Baltic proper. Kvarken is situated between the two. Together, the Bothnian Sea and Bay make up a larger geographical entity, the Gulf of Bothnia, ...

being arguably the largest plain in the

Nordic countries The Nordic countries (also known as the Nordics or ''Norden''; ) are a geographical and cultural region in Northern Europe, as well as the Arctic Ocean, Arctic and Atlantic Ocean, North Atlantic oceans. It includes the sovereign states of Denm ...

. The plain is made up smaller individual

sand Sand is a granular material composed of finely divided mineral particles. Sand has various compositions but is usually defined by its grain size. Sand grains are smaller than gravel and coarser than silt. Sand can also refer to a textural ...

and

clay Clay is a type of fine-grained natural soil material containing clay minerals (hydrous aluminium phyllosilicates, e.g. kaolinite, ). Most pure clay minerals are white or light-coloured, but natural clays show a variety of colours from impuriti ...

plains alternated with rivers and

peat bog A bog or bogland is a wetland that accumulates peat as a deposit of dead plant materials often mosses, typically sphagnum moss. It is one of the four main types of wetlands. Other names for bogs include mire, mosses, quagmire, and muske ...

s. It extends as a 100 km wide and 257 km long belt along the northwestern coast of Finland. The plain is extremely flat with height differences never exceeding 50 m. Geologically the plain is a continuation of the

Sub-Cambrian peneplain The sub-Cambrian peneplain is an ancient, extremely flat, erosion surface (peneplain) that has been exhumed and exposed by erosion from under Cambrian strata over large swathes of Fennoscandia. Eastward, where this peneplain dips below Cambrian an ...

found across much of

Fennoscandia __NOTOC__ Fennoscandia (Finnish language, Finnish, Swedish language, Swedish and ; ), or the Fennoscandian Peninsula, is a peninsula in Europe which includes the Scandinavian Peninsula, Scandinavian and Kola Peninsula, Kola peninsulas, mainland ...

References

{{coord missing, Finland Landforms of Ostrobothnia (administrative region) Landforms of North Ostrobothnia Plains of Finland