The large entrance hall, now opened by bright glass windows on the east and west sides, is the result of an extension that took place in the years immediately after 1507. This was originally a space outside the palace intended to ensure the continuity of the patrol walkway behind the walls and served mainly as a support for the rooms on the upper floor. The vast vaulted room appears to be bounded on one side by the powerful buttresses of the 16th-century walls, connected by barrel vaults and, on the opposite side, by the original exterior façade of the palace.
Two different decorative installations are particularly evident here: the large squared ashlars imitating a marble cladding are overlaid by a second type of ornamentation with five tall painted arches. Finally, a motif of small flames radiated all over the walls starting from the central oculus of the vault where the emblem of the crucible was depicted, an insignia particularly dear to Francesco II Gonzaga and a recurring element in the decoration of the entire palace.
