In Museum, many testimonies of our cultural heritage can be found. But because of their high fragility, the public can not get too close to them. In this communication we will explain a project that deals with a physical mock-up of Nantes harbor; the mock-up has been built in 1899 and shown in 1900 for the World's Fair that took place in Paris, France. This heritage object is nowadays at the "Château des Ducs" museum in Nantes, France, but shown behind panes. The object has been digitized and a 3D model has been reconstructed. Thanks to a virtual system coupled to a touchscreen with semantic research modules and to a light pointer, it will allow the visitor to better understand the mock-up and the associated history. Moreover, the system will be user-centered: the visitor will interact directly with the digital mock-up and obviously with all the knowledge that allows the contextualization.