Piazza Maggiore is a central square in Bologna, region of Emilia-Romagna, Italy. The appearance in the 21st century, generally reflects the layout from the 15th century. The Northwest corner opens into Piazza del Nettuno with its Fontana del Nettuno, while the Northeast corner opens into the narrower Piazza Re Enzo, running along the flanks of the Palazzo Re Enzo that merges with the Palazzo del Podestà. Flanking the Piazza del Nettuno is the Biblioteca Salaborsa.