During the last year, the University of Cagliari re-discovered an important collection of engravings by Giovanni Battista Piranesi, the venetian visionary architect of XVII century whose influence on artists and works lasts still nowadays. The collection has been forgotten for many years into some lost room, so that even its memory was difficult to find among university teachers, librarians or employees. We organized an exhibit to present to the citizens this public treasure, showing some of the over 1100 printings into the space of Il Ghetto, an exhibit centre in the ancient heart of Cagliari, called the Castello quarter. Together with architect Paolo Sanjust we looked after the graphic and exhibit design. A modern art exhibit inspired by Piranesi’s works, has also been organized near there, at the ancient City Hall.