 Tilbygningen is a new virtual extension to Thorvaldsens Museum making topical the art, life and museum of the Danish sculptor Bertel Thorvaldsen. Through multiple mediums, stories and views combined in a complex link structure Tilbygningen engages the museum guest actively. In this open structure constituted by interactive fiction films, creative projects by young people and factual articles, the museum guest is a co-creator of the framework and content of the museum extension. Both through her spontaneous movement within the structure and through her personal and creative additions to the Project Gallery in the extension.