Obviously we are very proud of the new Opera in Oslo, and it is definitely both original and spectacular.
You don't get the genius in the architecture before you enter the building though, you can walk on the roofs and the view from there is great. That building is very inspiring!
Also, I love the Munch Museum. The Norwegian artist left most of his work to the city of Oslo, and a visit to the museum always inspires me.
Right next to the museum is one of the most beautiful places in Oslo, The Botanical Gardens. I love to go there and just relax and look at all the flowers. In May the trees are in bloom, and it just looks incredible.