This little niche is described as the "kartoteket," which I believe translates as "the map library." It's really a beautiful art installation piece designed to house the library's picture archive (housed in the card catalog). "The artist Rikke Sund Carlsen has put together a series of small universes that explore the diversity and breadth of the [kartoteket]. The universes have now become an organic part of the [kartoteket]."