Here I want to make a list of some common art related mistakes about Florence.
1) Fontana del Porcellino, this fountain at Loggia del Mercato Nuovo is a replica (made by Fonderia Marinelli) of the famous fountain made about in 1633 by Pietro Tacca.
The base of the fountain was collocated in the Lapidarium of Museo di S. Marco in 1857, replaced with a replica by Giovanni Benelli and then restored by Elena Della Schiava from 2008 to 2010. The fountain was restored in 1998 and moved to the Bardini Museum. It is worth noting that Pietro Tacca’s fountain is itself a replica of an ellenistic marble Cinghiale now at the Uffizi: indeed the name Porcellino is improper, since the animal is a boar.
2) Giuditta e Oloferne, this bronze sculpture by Donatello was placed in Piazza della Signoria in 1494, but then moved to the Loggia dei Lanzi in 1504, to make place for Michelangelo’s David. The sculpture was then replaced with Ratto delle Sabine by Giambologna and moved again to the Arengario. After a restoration in 1988 it was placed in Palazzo Vecchio. The sculpture actually in the Piazza is a replica.
3) Façade of Duomo, the original façade, originally designed by Arnolfo di Cambio (with perhaps some contributions by Giotto) was left unfinished. It was then dismantled in 1587-1588 by Bernardo Buontalenti. A competition for a new façade took place in 1861, but there was no winner. A second competition followed in 1864, and it was won by Emilio de Fabriis, but his proposal was debated. So there was a third competition in 1865, again won by de Fabriis in 1867, who then defined all the details of his project in the following two years. The final project was approved in 1870 and on July 4 de Fabriis became “architect of the façade of Santa Maria del Fiore”. Luigi del Moro continued the work after de Fabriis died in 1883, and the façade was completed in 1887.
4) Orsanmichele, the sculptures in the 14 niches of the façades are all replicas. The originals are all in the Museo di Orsanmichele, except the S. Giorgio by Donatello, which in 1891 was moved to the Bargello.
5) Porta del Paradiso, the east doors of the Baptistery are replicas. Vasari wrote that Michelangelo said about these doors elle son tanto belle che elle starebbon bene alle porte del Paradiso (they are so beautiful that they would be fine at the heaven’s doors). The door was removed in 1943 to save it from bombardments and then placed again in the Baptistery in 1948. After the damages provoked by the flood in 1966, it was moved to the Museo dell’Opera del Duomo. The restoration was completed in 2012.
6) Marzocco, this sculpture made by Donatello in 1419-1420 is actually at the Museo del Bargello. The one visible in the Piazza is a replica. The Marzocco is a heraldic lion symbol of Florence.
7) All the historic bridges that you see nowadays in Florence (with the exception of Ponte Vecchio) were rebuilt after being mined by the Nazis on the night between August 3 and 4, 1944: Ponte San Niccolò, Ponte alle Grazie, Ponte Santa Trinita, Ponte alla Carraia, and Ponte alla Vittoria.
8) Mona Lisa, the correct name is Monna Lisa, with two n. Monna is the diminutive of Madonna, which means mia donna (literally, my woman). It derives from the latin mea domina and is equivalent to the french madame. Mona (with a single n) in the venetian or milanese dialects is used to indicate a stupid person or the female genitals.
9) Façade of Santa Croce, the façade was designed by Niccolò Matas, and made between 1853 and 1863.