The basement is located in the inner courtyard of the Institute. Lined with concrete only in the first section, at lower elevations it is dug into bare rock.
The tunnel has a uniform cross-section (280 cm wide by 230 cm high) and a rudimentary electrical system with Bakelite lamp holders running in sections along the tunnel. The State Archives of Cagliari preserve the correspondence between the Rector of the Institute and Prefect Leone regarding the huge expenses for the construction of the shelter, “useful for everyone.”
However, the institute would have been willing to bear the costs of water, lighting, cleaning and maintenance; a request granted, so much so that the Salesian shelter was built entirely by the state.
The project, under the direction of Eng.
Carlo Ansaldi, called for 56 m long by 2.50 wide and 2.50 high, with wooden footings, seats and gates.
The May 13, 1943 bombing destroyed the room of the soldiers of the National Committee of Aircraft Protection serving at the shelter.
The report of May 15, 1943 gives a list of items (weapons, personal belongings, linens, items that were in the soldiers’ dormitory on duty on Friar Ignatius Avenue at the Salesians) whose total or partial damage or integrity is specified.
