The rectangular hall leading to the southern staircase belongs to a series of rooms in the western wing, where paintings are used to create an extremely symbolical place, to be considered as the ideal starting point for an initiation to the itinerary which leads from the staircase to the tower.
The interior decoration of the venue consists of a series of ionic pilasters supported by a continuous base, and which also support a protruding frieze adorned with corbels and floral friezes, in turn surmounted by a paneled vault. The fresco decorations act as cornices also of the doors leading to the room, and are adorned with garlands and cupids leaning on marble recesses. On the western side are two cupids holding some books, a lantern and an arrow, representing in this manner, Genius based on Constancy and Intelligence. On the southern side, all traces of cupids have been lost, while on the northern wall, there is one with a medal in hand, a symbol of Honour. Beneath this appears a Latin inscription unfortunately only in fragments, with the date “Year MDCLIX” (1659) and a reference to the nomination of Bartolomeo III Arese as Senate President, which took effect the following year. This date is particularly important also because it coincides with the coming to adulthood of the heir of Bartolomeo, Giulio II Arese, and the year in which the Peace of the Pyrenees Pact was sealed, and that put an end to the conflict between the reigns of Spain and France, allowing Bartolomeo to “lighten” also his political obligations.
Critiques attributed the paintings to the Milanese painter, Giovanni Ghisolfi (1623-1683), trained in Rome in the workshop of Salvator Rosa and who worked on most of the rooms on the first floor of the noble mansion. He carried out the works here in a sober way without any kind of exaggeration, probably with the intent of creating a modest venue that would act as the best pre-chamber to the marvels contained in the adjacent rooms, especially the Hall of Roman glory.