On our last morning in Oslo, we visited the cathedral. Seems like it had been closed when we tried to go before. It was consecrated in 1697 and restored to its original baroque interior in 1950. Oslo Cathedral is the main church for the Church or Norway, Diocese of Oslo, as well as the parish church for downtown.
I don’t know exactly what this was, but it was covered with mosaic that reflected the church on one side and projected a light display on the wall from the other. There were also many handles on the sides, pictured here. Very unusual, whatever it was.
The whole artwork, posted earlier: