Mosaics to visit in Italy
Ravenna: Basilica of San Vitale, Basilica of Sant'Apollinare in Classe, Basilica of Sant'Apollinare Nuovo, Battistero degli Ariani, Battistero Neonianoi, Domus dei Tappeti di Pietra, Galla Placidia Mausoleum, St Francis, St Agatha, Archiepiscopal Museum & Chapel, Neonian/Orthodox Baptistry, Arian Baptistry, Bascilica of St John the Evangelist and the Park of Peace (modern mosaics). I can't recommend a visit to Ravenna enough it is the mosaic capital of the world with outstanding examples of Roman and golden Byzantine mosaic art dating back to the 5th century within its religious buildings.
Venice: Basilica of San Marco. Mosaics include St Mark's body being carried to the basilica.
Torcello, Venice: Santa Maria dell'Assunta. Doomsday mosaics illustrating the Last Judgement.
Monreale (Sicily): Cathedral. Magnificent 12-13th century gold mosaics illustrating the New & Old Testament.
Palermo (Sicily): Capella Palatina, La Martorana, San Cataldo, Palazo dei Normanni, Archaeological Museum. Religious mosaic art and floor mosaics from digs at Palermo, Solunto & Marsala.
Cefalu (Sicily): Cathedral. Fantastic gold mosaics featuring Christ the Pantocrator in the apse.
Piazza Armerina (Sicily): Villa del Casale. Exceptional Roman mosaics decorate each room highlighted by the Hall of the Female Gymnasts in Bikinis.
Naples: Archeaological Museum housing illustrative mosaics such as The Battle of Alexander from the House of the Faun in Pompeii. Further mosaics dating from 2nd century are on display from digs in Pompeii, Stabiae, Herculaneum & Boscoreale.
Pompeii: House of the Labyrinth. Mosaic floor representing Theseus & the Minotaur in the Labyrinth.
Herculaneum: Featuring the geometric patterned mosaics of the House with the Mosaic Atrium and House of the Neptune and Amphitrite Mosaic in the summer dining room.
Rome: Capitoline Museums, Santa Maria del Popolo, Museuo Nazionale Romano, Santa Maria Maggiore, Bascilica of St Peter, Santa Maria in Trastevere, Santa Maria in Domnica. Great examples of early Roman mosaic art in the Capitoline and Vatican Museums.
Trieste: Duomo. 13th century apse mosaics
Florence: Duomo & Baptistry, San Miniato al Monte. 13th century mosaics adourn both, the latter has an outstanding facade and zodiac and animal mosaics within.
Lucca: San Frediano. The Apostles in The Ascension feature on the facade.
Sarsina: Sarsina Museum. 1st century floor of a Roman bath house.
Palestrina: Palestrina Museum. Mosaic marbled floor of Temple of Praeneste, 2nd century BC.
Otranto: Cathedral. Huge tree of life floor mosaic.
Aquileia: Cathedral. 4th century mosaics marking the transitional period of Constantine the Great.
Mosaic Artist (UK based)