Abstract
This research deals with Giovanni Battista Piranesi's attitude as an architect for Santa Maria del Priorato. The church contains twelve round-shaped medallions, out of which the apse has two beneath the cornice. This paper, in particular, categorizes them as a type of "suspended medallion," and pursues its precursor, examining the architect's traces of medallions in his drawings of architectural fantasies and capricci produced between the 1740s and the 50s. As a result, it is assumed that the medallion is ascribed to Filippo Juvarra's festival design on the motif of la Piazza del Campidoglio in 1713.