The Gothic-style sandstone structure is made up of three massive statues, representing Gutenberg and his printers and patrons, Hans Fust and Peter Schöffer. The main causes for the invention of the time-honoured art of book-printing - theology, poetry, natural sciences and industry - are represented as allegorical figures, sitting at the corners of the memorial's base, which in turn is adorned by a frieze featuring the busts of famous printers, publishers and booksellers. The crests depicted stand for Mainz, Strasbourg, Frankfurt and Venice, the cities where printing first left its mark in modern times.