Kongens Utsikt (The King's View).
Kongens Utsikt offer excellent views of Tyrifjorden lake, and is a easy hiking day trip out of Oslo. Take the number 200 bus from St Olavs Plass, and get off at Sundvollen, hike the 1.3km uphill train to Kleivstua and then follow the signposts to the viewpoint.
The King's View as seen at the end of August. Photo. I det fri/Flickr
The more intrepid can cycle the whole journey from Oslo, including the challenging climb at the end.
Luttvannet and Nøklevannet
Nøklevannet in the Østmarka countryside just to the east of Oslo once supplied all of the city's water. But today, it's a popular weekend and afternoon getaway from the city. Take metro 3 (Mortensrud) to Ulsrud station and you can then walk a 7.8km look past the lake to Mariholtet Sportsstue, where you can warm up over coffee and sandwiches. See the trek in more detail on the Outtt hiking app.
Photo: Kjetil Ree/Wikimedia Commons
Østernvann in early spring. Photo: Bjoertvedt/Wikimedia Commons.
One of the most popular nature areas around Oslo, Sognsvann, the last stop on line 5 of the Oslo T-bane, is a great place to experience autumn, with its copious birch trees turning yellow and brown. The walk around the lake is only 3.2km making it suitable for families with small children. If you want a longer walk, you can continue on the far side out to the Ullevalseter hiking centre where you can replenish your energy with coffee and buns.
A group on a walk around Sognvann. Photo: Espen Bratlie/Visit Oslo
The Botanical Garden in Tøyen, with its arboretum filled with all manor of trees from across the world, is a wonderful place to visit as maples and other trees turn orange and gold. The gardens are currently decorated with woven sculptures by the British artist Tom Hare. The gardens are an oasis of greenery in central Oslo and are just a short walk from the central train station.