The entire installation plays with one's perceptions, both intellectual (historical) and physical (aural, visual). "O Belgrade!" remembers the region's history, with the reference to the cutting of the local forests in ancient times by foreign occupiers, the matrilineal cults that spanned southeastern Europe, and Serbia's continuing cultural contacts with the world from the Vltava to the Pacific Ocean. Now free, after a long, brutal war, and before that years of communism, the question stands for Serbs: how to fill up and empty cage?