The expansion to the National Museum Zurich complements the original museum building of 1898 designed by the architect Gustav Gull. The new building directly incorporates some of the context’s existing features into its architecture. The building’s layout accommodates the trees and paths of the historical park, and the characteristic roofscape of the old building sets the volumetric theme of the new structure. The expressive folds in the rooftops can be understood as a contemporary interpretation of Gull’s articulated Historicism. The new is thus inconceivable without the old, but is nonetheless unmistakably modern. Architecturally the ensemble consists of two very different aspects: the graceful, historical old building designed in an open U shape and the sculptural character of the new wing that closes off the existing building complex thereby enabling continuous movement through both the old and new sections. As different as the new and old buildings are, their similarities and shared architectural attributes are abundantly apparent and serve to create a unity of old and new. The strong stone walls of the old 19th-century building are echoed in the new wing’s 80-centimeter thick walls, which fulfil the high thermal insulation requirements of the Minergie-P Eco standard. The tuff concrete developed especially for use in the new wing corresponds to the tuff facade of the old building, and the polished concrete floors in the new wing suggest a modern interpretation of the decorative terrazzo floors in the old building. Concrete dominates in the interior of the new museum. Combined with the technical elements purposely left exposed on the ceilings, this creates an almost industrial-like atmosphere that is robust, spacious and open to a variety of forms of exhibition and presentation. The new spaces at the National Museum Zurich are conceived as museum factory halls – conservational and at the same time experimental.