Oslo

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• Schleswig-Holstein
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History

During the Viking Age, the area that includes modern Oslo was located in Viken, the northernmost province of Denmark. Control over the area shifted between Danish and Norwegian kings in the Middle Ages, and Denmark continued to claim the area until 1241. According to the Norse sagas, Oslo was founded around 1049 by Harald Hardrada. Recent archaeological research, however, uncovered Christian burials which could be dated to prior to AD 1000, evidence of a preceding urban settlement. This called for the celebration of Oslo's millennium in 2000 rather than 2049. Under the reign of Olaf III of Norway (1067–1093), Oslo became a cultural centre for Eastern Norway. Hallvard Vebjørnsson became the city's patron saint and is depicted on the city's seal. In 1174, Hovedøya Abbey was built. The churches and abbeys became major owners of large tracts of land, which proved important for the city's economic development, especially before the Black Death. At the end of the 12th century, Hanseatic League traders from Rostock moved into the city and gained major influence in the city. On 25 July 1197, Sverre of Norway and his soldiers attacked Oslo from Hovedøya. During the Middle Ages, Oslo reached new heights during the reign of Haakon V of Norway (1299–1319). He was the first king to reside permanently in the city, and it has been regarded as the capital city of Norway since his reign. He also started the construction of the Akershus Fortress and the Oslo Kongsgård. The Black Death came to Norway in 1349 and, like other cities in Europe, the city suffered greatly. The churches' earnings from their land dropped so much that the Hanseatic traders dominated the city's foreign trade in the 15th century. In 1380, Norway was the weaker part in a personal union with Denmark, and…

Geography

Oslo occupies an arc of land at the northernmost end of the Oslofjord. The fjord, which is nearly bisected by the Nesodden peninsula opposite Oslo, lies to the south; in all other directions Oslo is surrounded by green hills and mountains. There are 40 islands within the city limits, the largest being Malmøya (), and scores more around the Oslofjord. Oslo has 343 lakes, the largest being Maridalsvannet (). This is also a main source of drinking water for large parts of Oslo. Although Eastern Norway has a number of rivers, none of these flow into the ocean at Oslo. Instead Oslo has two smaller rivers: Akerselva (draining Maridalsvannet, which flows into the fjord in Bjørvika), and Alna. The waterfalls in Akerselva gave power to some of the first modern industry of Norway in the 1840s. Later in the century, the river became the symbol of the stable and consistent economic and social divide of the city into an East End and a West End; the labourers' neighbourhoods lie on both sides of the river, and the divide in reality follows Uelands street a bit further west. River Alna flows through Groruddalen, Oslo's major suburb and industrial area. The highest point is Kirkeberget, at . Although the city's population is small compared to most European capitals, it occupies an unusually large land area, of which two-thirds are protected areas of forests, hills and lakes. Its boundaries encompass many parks and open areas, giving it an airy and green appearance. Oslo has a humid continental climate (Köppen climate classification: Dfb) or, if the original Köppen winter threshold is used, an oceanic climate (Cfb) bordering on a humid continental climate in the 1991–2020 base period. Oslo has some of the warmest summers of Norway and fairly cold winters. Oslo receives a fair…

Most-observed species

• Great Tit

  Parus major Linnaeus, 1758 · Aves
  27,501
• Eurasian Blue Tit

  Cyanistes caeruleus (Linnaeus, 1758) · Aves
  25,870
• Eurasian Blackbird

  Turdus merula Linnaeus, 1758 · Aves
  25,672
• Eurasian Magpie

  Pica pica (Linnaeus, 1758) · Aves
  23,773
• Hooded Crow

  Corvus cornix Linnaeus, 1758 · Aves
  20,790
• Mallard

  Anas platyrhynchos Linnaeus, 1758 · Aves
  18,265
• European Greenfinch

  Chloris chloris (Linnaeus, 1758) · Aves
  17,715
• Common Wood-Pigeon

  Columba palumbus Linnaeus, 1758 · Aves
  16,267

Most recent

• M 3.9 — 2026-04-26
  1 km SSE of Sørumsand, Norway
• M 2.9 — 2008-05-25
  4 km WSW of Åneby, Norway
• M 2.6 — 2005-01-29
  7 km NNE of Hvittingfoss, Norway
• M 2.6 — 2004-12-29
  10 km WNW of Flateby, Norway
• M 3.4 — 2004-04-07
  11 km N of Sand, Norway