A multi purpose arena/sport complex that offers increased amounts of fun both during the summer and the winter. In the warm season it hosts a roller-blade practice ground for all ages, while in the winter it turns into an ice skating rink, with a special track for speed skating. It is also a place where one can practice inner bandy and that actually hosted few editions of the World Championships. The way the hall is built also allows it to host soccer games. The venue usually opens in November for skating and they are listing their schedule on this link.
During both seasons, Valle Hovin is one of the largest concert venues in Oslo, able to hold about 40k people, both standing and seated. Among the names that held concerts there I could mention Pink Floyd, Metallica, Rammstein, U2, Michael Jackson, AC/DC. And I personally believe that a big advantage of this venue is its proximity to the city center, only few subway stations away from the Central Station. That is Helsfyr Subway station. There’s also few busses taking you right next to the entrance, but I recommend the subway for the very busy events when the traffic around the area is almost impossible due the flow of people on streets.