The Libraria of Collegium Maius used to be the University library. In the western part of the room, there are reconstructions of instruments that were once used by astronomers, including the University’s famous graduate, Nicolaus Copernicus, such as the spherical astrolabe, otherwise called ‘armillary sphere’, the quadrant and the triquetrum, also known as ‘parallactic ruler’ or ‘Ptolemy’s ruler’. 

To this day, Libraria hosts important conferences and meetings of the University professors. It is also here that the Senate of the Jagiellonian University regularly meets.