Telemark [ˈtêːləmɑrk] (listen) is a traditional region, a former county and a current electoral district in Norway. In 2020, Telemark merged with the former county of Vestfold to form the county of Vestfold og Telemark. Telemark borders the traditional regions and former counties of Vestfold, Buskerud, Hordaland, Rogaland and Aust-Agder.
The various geographic sub-regions of Telemark have distinct cultural traditions in terms of dialect, music, clothing, handcrafts, food, and architecture.
In the Middle Ages, the agricultural society of Upper Telemark was considered the most violent region of Norway. Today, half of the buildings from medieval times in Norway are located here. The dialects spoken in Upper Telemark also retain more elements of Old Norse than those spoken elsewhere in the country. Upper Telemark is also known as the birthplace of skiing.
Telemark has been one of Norway's most important industrial regions for centuries, marked in particular by the Norske Skog Union paper mills in Grenland and the Norsk Hydro heavy water and fertilizer production in Upper Telemark.