The Oslofjord (, ;
The bay is divided into the inner (indre) and Ytre Oslofjord (ytre) Oslofjord, separated by the long by wide Drøbak Sound. The innermost part is known as Bunnefjorden.
Fjord
From 1624 until 1925 the name of the fjord was Christianiafjorden (or Kristianiafjorden), since Christiania was the name of the capital during this period (the
Ch was changed to a
K in 1877). Before that time, the
Old Norse name of the fjord was Fold. The old name
Fold led to the names of the counties of
Vestfold ('the district west of Fold') and Østfold ('the district east of Fold') as well as the nearby district of Follo.
Geography
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
Aker Brygge. Hovedøya is known for containing 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.
Climate
The Oslofjord has Norway's highest all year temperature: . February is the coldest month in the fjord with , while July normally reaches . The islands in the middle of the fjord are among Norway's warmest with high summer temperatures and moderate winters. The Oslofjord's relatively high temperatures enable various flora to flourish.
History
The oldest settlements in the area surrounding the Oslofjord date from the
Stone Age and the
Bronze Age. It was here on the eastern and western shores that three of the best preserved Viking ships were unearthed, including the
Gokstad ship. In historical times, this bay was known by the current name of the region, Viken ().
Oslofjord has been an important body of water strategically due to its proximity to the capital city of Oslo. During World War II, there were Germany installations at several points on its coastline. One installation in Hovedøya held 1,100 Wehrmacht soldiers and later women deemed Nazi Collaborationism at the National Internment Camp for Women in Hovedøya.
Norwegian painter Edvard Munch had a cottage and studio in Åsgårdstrand on the fjord and the Oslofjord appears in several of his paintings, including The Scream and Girls on the Pier.
Second World War
The fjord was the scene of a key event in the German invasion of Norway in April 1940, the Battle of Drøbak Sound. The invasion plan envisaged landing of 1,000 troops transported by ship to Oslo.
Birger Eriksen, Commander of the Oscarsborg fortress near Drøbak, mainly maintained for historical purposes, sank the German
heavy cruiser Blücher in the Drøbak narrows.
The fortress's resistance blocked the route to Oslo, thus delaying the rest of the invading group long enough for the Norwegian royal family, government, parliament, and national treasury to evacuate. Thus Norway never surrendered to the Germans, leaving the Vidkun Quisling government illegitimate and permitting Norway to participate as an ally in the war, rather than as a conquered nation.
Demographics
The entire population situated around the Oslofjord including Oslo is about 1.96 million, and the total population of all the counties situated around the fjord is approximately 2.2 million.
More than 40% of Norway's population resides under 45 minutes of driving from the Oslofjord.
Although the Oslofjord contains hundreds of populated islands, most of the population of the fjord resides on the mainland.
Recreation
In the summer there are boats of all sizes on the fjord, and it is possible to go kayaking, canoeing, fishing, and sailing.
The Oslofjord is one of the nine venues of the Class 1 World Powerboat Championship.
Media gallery
Oslofjord Holmenkollen 2008.jpg|Oslofjord seen from Holmenkollen.
Oslojord from Ekeberg.jpg|Oslofjord seen from Ekeberg, in Oslo.
7oslofjord.jpg|Boats in the fjord mid-2006.
Fjordoslo.JPG|Oslofjord from Oslo-Copenhagen ferry.
