I walked down to the Oslo Opera House (“Operahuset” in Norwegian). The walk to the top was slippery as heck. I should have realised it was a bad idea to walk up there when I had to walk past a sign warning not to walk up there and clamber underneath a chain blocking access. But other people were chugging their way up, so I headed up the ridiculously slippery slope to the top and got an awesome view out across the fiord.