The design of the interiors of a private house for a collector of exceptional modern artworks was approached by Pierluigi Cerri as a challenge to combine the dimension and comfort of domestic spaces with the need to bring out the best in the art collection in terms of visibility and enjoyment. One of the spaces of the house has been connected to the area below it by means of a large opening made in the floor slab, linking the two zones on two levels in a single environment and creating a light, linear balcony with a tempered glass balustrade, free of support structures. Inside the rectangular opening in the slab, with large circular skylights above it to bring daylight into the house, a spiral staircase made by Marzorati Ronchetti connects the levels. It is designed as an essential mirror-finish steel sculpture around a central pillar of the same material, creating an effective play of reflections and anamorphic deformations that capture the images of the artworks around it.