, Italy, the capital of Pisa Province. It is on the Arno River, 6 miles (10 km) east of the Ligurian Sea—part of the Mediterranean—and 165 miles (265 km) northwest of Rome. Pisa, an important commercial city since the Middle Ages, now produces machinery, cotton textiles, glass, drugs, and pottery.
The University of Pisa was established in the 14th century. Galileo was a student and later a lecturer there. Pisa also has a museum of natural history, a library, and a botanical garden. In the northern part of the city is the Piazza del Duomo, a square containing four buildings of historic and architectural note. These are the 11th-century Romanesque cathedral, the 12th-century Baptistery, the 15th-century Camposanto, and the famous Leaning Tower.
The Camposanto, a rectangular building surrounding the cathedral cemetery, contains frescoes and ancient Roman sculpture. The Leaning Tower, the cathedral's campanile (bell tower), is a cylindrical marble structure 179 feet (55 m) high. It was completed in the 14th century. Owing to an unequal settling of the foundation, it began leaning while under construction. Its inclination increased by a very small amount each year, until by 1993 the top overhung the base by about 16 feet (5 m). The tower's lean was then reduced slightly by installing lead ingots to counterbalance the overhanging part of the tower. The lean was further reduced from 1999 to 2001 by gradually extracting small amounts of soil from underneath the tower, allowing it to settle more evenly.
Pisa was probably founded by the Greeks. It was later an Etruscan city and was conquered by the Romans in 180 B.C. During the Middle Ages it was an independent city that conquered Corsica, Sardinia, and the Balearic Islands. Pisa was defeated in a naval battle by Genoa in the 13th century and fell under the control of Florence in the early 15th century. In 1860 Pisa joined the newly established Kingdom of Italy.