The Manica Lunga has been built in the first half of the ‘ 600 by the Castellamonte architects, Amedeo and its son Carl for the Duke Carlo Emanuele I. In the illustrations of the Theatrum Sabaudiae, this longand strait building , at that time connected with the Castle was used to host the gallery of pictures of the Duke. It has been damaged , like all the complex, by the French troops of General Catinat in 1693, and it would have been destroyed in order to answer to the requirements of the new plan elaborated from Filippo Juvarra that previewed to its place a symmetrical building with at the center the great entrance hall and ball room at the first floor. The plan was interrupted before the demolition of the Manica Lunga, and from that moment it was used as service space, while in 1800 with the definitive passage of the Castle to the Rivoli City it hosted the soldiers used as a barrack. While after the II World War it became residence of the evacuated. These improper utilisations modified the structure with the building of of new spaces for hygienic services, like it is possible to see in the the photographies that document the situation of degradation and abandonment of all the’ building. The restoration of the Manica Lunga started in 1986, date that it possible to see on the façade, and finished definitively in 2000 with the opening of the exhibition space at the third floor . With these intense activities, the exhibition vocation of the space returns to being valued, at the extirior Andrea Bruno, l’ architect at the centre of the restoration intense activity, has placed the staircases and the’ elevator, realized with transparent materials that give the possibility to observe better the structure, long 147 meters and wide 6. The metallic cover, realized ex novo, is connoted by the repetition of centres, with a central cap all along the length of the structure, the light has been brought back thanks the elimination of the attics and the structures realized in more recent to time and not pertaining ones to the Castellamonte period. The opening of large windows at head of all the plans increases the light remarkablly, permitting to see the Castle.