Oslo Opera House Building In Norway - Winter 2017 (February) architectural tour inside and out. Quick Oslo travel guide video tip for what to do in Norway. With Edvard Grieg's "In the Hall of the Mountain King" playing in the background. The Oslo opera is located at the short streets Kirsten Flagstads Plass 1 and Operagata (Opera street) and is impossible to miss, night or day. Completed 10 years ago in 2007, the Oslo opera house was designed by Snøhetta architecture, and is the home to the Norwegian National Opera and Ballet.