The project maintains the current entrance through the public gallery and the north courtyard, which is furnished for the reception, café and shop services, currently confined to the central foyer. In order to include the north courtyard in the usable floor space, it will be roofed with an inflated translucent Low-E ETFE membrane bubble. This self-supporting canopy is anchored to the courtyard perimeter on the building's top ledge by means of a steel perimeter structure. The southern courtyard, on the other hand, will remain an outdoor space, free of restrictive uses. Its floor consists of 2" diameter pebbles set in sand, like the material found in recent archaeological excavations on the site. The entrance hall between the courtyards is freed in order to hold the vertical circulations that lead to each of the museum's four levels. The largest exhibition hall, measuring 38x11x7 metres, and the storage rooms beneath it are located underground, traversing the length of the building in a unique itinerary called 'Chile before Chile'. Its large size, or rather its lack of definition, will give the museum's exhibition rooms a new scale. A natural penumbra will prevail here, nuanced by light entering through two skylights at each end. It will be built in concrete, stained charcoal grey, and dark IPE wood. Its edges will be blurred on account of the shadows, accentuating its excavated or subterranean condition. The visitors' attention will be focused naturally on the spotlit display items.