Flanked by grand 19th-century neoclassical colonnades, this landmark piazza was laid out as part of Rome’s post-unification makeover. It follows the lines of the semicircular exedra (benched portico) of Diocletian’s baths complex and was originally known as Piazza Esedra.
The elegant Fontana delle Naiadi, built in 1888, was designed by Alessandro Guerrieri, who decorated it with four lions; they were replaced by sculptor Mario Rutelli's bronze nymphs in 1901, which aroused puritanical ire when unveiled. The nudity of the four naiads, or water nymphs, who surround the central figure of Glaucus wrestling a fish, was considered too provocative – how Italy has changed! Each reclines on a creature symbolising water in a different form: a water snake (rivers), a swan (lakes), a lizard (streams) and a seahorse (oceans).