At the end of the two-flight grand staircase, a portal is decorated with an inscription in capital letters bearing the name of Giovanni Sforza.
On the left of the porch is the antechapel, a spacious environment, its original purpose unknown but it is thought that it was used as a place of service, maybe barn or warehouse, as can be understood from the current flooring, under which were found bumpy cobblestones, not suitable to be used as a place of residence.