We are so lucky to have another guest blogger. This photo is by André and his photo is from the river that devides Oslo in two: Akerselva river.
The river starts from the large lake Maridalsvannet (which also is the drinking water for a large part of Oslo's population). The river runs for 8.2 kilometers before it ends in the Oslo fjord and offers nice walks for those who are interested:
Follow the river Akerselva from Maridalsvannet to the centre of Oslo.
8 km with recreation, through forests and old history, fishing, swimming and several waterfalls. The highest waterfall is next to "Hønse-Lovisas hus", a small, red house, and the Beier bridge.
Here's a page about Winter Walk along the river Akerselva. And here's yet another page about the river walk for tourists in Oslo.