Oslo's fabulous opera house is a real architectural feat, with part of the building below sea level. It was awarded the European Union's Prize for Contemporary Architecture in 2009. This huge Carrara marble-covered block emerges like an iceberg from the fjord and glints like a great diamond with the slightest ray of sun. Visitors can climb up it, walk on it, or use it as a beach, ski slope or panoramic lookout. It is home to the opera company and National Ballet.