Oslofjord

The Oslofjord (Norwegian: Oslofjorden, English: Oslo Fjord) is an inlet in the south-east of Norway, stretching from an imaginary line between the Torbjørnskjær and Færder lighthouses and down to Langesund in the south to Oslo in the north. It is part of the Skagerrak strait, connecting the North Sea and the Kattegat sea area, which leads to the Baltic Sea. The Oslofjord is not a fjord in the geological sense - in Norwegian the term fjord can refer to a wide range of waterways. The bay is divided into the inner (indre) and outer (ytre) Oslofjord at the point of the 17 by 1 kilometre (10.56 by 0.62 mi) Drøbak Sound.

In the period 1624-1925 the name of the fjord was Kristianiafjorden (or Christianiafjorden) - since this was the name of the capital in this period. The old Norse name of the fjord was Fold, giving names to the counties of Vestfold ('the district west of Fold') and Østfold ('the district east of Fold') - and also the district Follo.

Each of the islands in the innermost part of the fjord has its own identity and distinguishing history. Among them are Hovedøya, Lindøya, Nakholmen, Bleikøya, Gressholmen, and Langøyene. These islands can be reached with the Oslo-boats from Vippetangen. Hovedøya contains monastery ruins, Gressholmen for its rabbits, Nakholmen, Bleikøya, Lindøya for their cosy cabins at the water’s edge, and finally Langøyene for its camping possibilities and beach.

The inner part of the Oslofjord has steep and forest covered hill slopes down towards the fjord.

The Oslofjord has Norway’s highest all year temperature: 7.5 degrees Celsius. February is the coldest month in the fjord with -1.3 degrees Celsius, while July normally has 17.2 degrees Celsius. The islands in the middle of the fjord are among Norway’s warmest with high summer temperatures and moderate winters. Oslofjord’s relatively high temperatures enable various flora to flourish.

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Wikipedia