Pisa is a small Tuscan city of about 90,000 people on the River Arno, 80 km west of Florence and just inland from the Ligurian Sea. For most of the 11th, 12th and 13th centuries it was one of the four great maritime republics of Italy, along with Venice, Genoa and Amalfi, and the extraordinary ensemble of buildings on the Campo dei Miracoli (the "Field of Miracles") dates from the height of that power — a glittering assembly of white marble cathedral, baptistery, bell tower and cemetery on a single lawn, each one a first-rank masterpiece of Italian Romanesque architecture.
The Leaning Tower (Torre Pendente), built between 1173 and 1372 as the freestanding bell tower of the cathedral next door, is of course the one everyone comes for. It started tilting during construction, as its foundations settled unevenly into the soft alluvial soil; a decades-long stabilisation project in the 1990s and 2000s managed to straighten it by 45 cm without destroying the lean, and it is now considered safe to climb. Book tickets well in advance. Next to it, the Duomo (cathedral) is the single finest Pisan-Romanesque building in the world, with Nicola Pisano's extraordinary hexagonal pulpit (1260) inside. The circular Baptistery has the best acoustics of any building in Italy — the custodian periodically demonstrates by singing a chord that echoes for half a minute — and the Camposanto cloister is lined with 14th-century frescoes damaged in an Allied bombing in 1944 and slowly being restored.
Beyond the Campo dei Miracoli, most visitors never venture, which is a shame. The rest of Pisa is a pleasant, quiet, un-touristy university town with a busy student population, good cheap restaurants, and some genuinely worthwhile sights: the Piazza dei Cavalieri laid out by Vasari for the Medici, the small Gothic riverside chapel of Santa Maria della Spina, and the excellent Museo Nazionale di San Matteo with its collection of 12th–15th century Tuscan panels. Pisa International Airport, just south of the old town, is one of the main budget-airline hubs for Tuscany. Most visitors see Pisa as a day trip from Florence (an hour by train), combined with nearby Lucca, but an overnight stay lets you see the Campo dei Miracoli at dawn without the crowds.