PISA, a town and archiepiscopal see of Tuscany, Italy, capital of the province of Pisa, on the Arno, 7 m. from the sea, and 49 m. W. of Florence by rail. Pop. (1931) 31,215 (town), (commune). It retains its mediaeval walls, 61 m. in circuit; the citadel now contains barracks. The cathedral, the baptistery, and the famous leaning-tower form a group by themselves at the north-west corner of the town. The two former are built in black and white marble, a characteristic found in Pisan churches elsewhere also. (See SARDINIA. ) The architects of the cathedral were Buschetto and Rinaldo, both probably Pisans. The church is in plan a Latin cross, 311; ft. long and 252 ft. wide across the transepts inside. The nave, 109 ft. high, has double, the transepts single, vaulted aisles : and at the intersection of nave and transepts is a dome. The columns of the nave and side aisles are ancient. The west front is the finest part of the exterior : the range of arches running round the base is repeated by four open arcades. The three bronze doors were re-made after the fire of 1596; that of the south side 18o) is by Bonanno. The mosaics in the apse were designed by Cimabue, and the splendid decagonal pulpit (restored in 1926: see Per la recostruzione del per gamo di Giovanni Pisano, 1926) is by Giovanni Pisano. The bap tistery, begun in 1153, is a circle Ioo ft. in diameter and is cov ered with a cone-surmounted dome 190 ft. high on which stands a statue of S. Ranieri. The lowest range of semicircular arches consists of 20 columns, and the second of 6o; and above this is a row of f8 windows in the same style separated by as many pilasters. In the interior, which is supported by four pil asters and eight columns, the most striking features are the octagonal font and the hexagonal pulpit, erected in 1260 by Nic cola Pisano. The campanile or "leaning tower of Pisa," begun by Bonanno in 1174, is round. The walls at the base are 13 ft.
thick, and at the top about half as much; they are constructed throughout of marble. The base ment is surrounded by a range of semicircular arches supported by 15 columns, and above this rise six arcades with 3o columns each. The eighth storey, which contains the bells, is of much smaller diameter than the rest of the tower, and has only 12 columns. The height of the tower is 179 feet. The tower was 15; ft. out of the perpendicular when measured in 1829, and 16; ft. in 1910. There is no reason to suppose that the architects intended that the campanile should be built in an oblique position; it would appear to have assumed it while the work was still in progress.
The foundations are not more than ft. deep, and their circum ference only that of the tower. The Campo Santo, lying to the north of the cathedral, owes its origin to Archbishop Ubaldo (1188-1200) who made the spot peculiarly sacred by bringing 53 shiploads of earth from Calvary. The building, erected in the Italian Gothic style by Giovanni Pisano in 1278-83, is of special interest for its famous frescoes by various Tuscan artists, includ ing a "Last Judgment" by Francesco da Volterra after Orcagna (1370-71) ; Benozzo Gozzoli (23 Old Testament scenes, 1468 84), and also for the large collection of Roman sculptures which it contains. Other notable churches are: S. Andrea, S. Pierino, S. Michele in Borgo (I ith century), S. Sepolcro, erected by Dio tisalvi (c. 1150), S. Nicole, with a four-storied tower (c. 1230), S. Caterina (1252), S. Francesco (13th century) with frescoes by Taddeo Gaddi (in the adjacent monastery is the interesting museum and picture gallery) ; S. Maria della Spina, an elegant little church of white marble (1325-29) ; and the Renaissance church of the Tuscan order of St. Stephen from plans by Vasari (after 1562), who also reconstructed the palace of the order.
The main streets of the older part of the town have porticoes. There are wide quays, with fine buildings, on each side of the Arno, but the town, as a whole, is quiet, owing much of its im portance to its being the junction for Florence, Lucca, and Vol terra, on the main line between Rome and Genoa. The uni versity, founded in 1338, had 1,096 students in 1925-26; it has a natural history and other museums and a botanical garden. There is also an engineering school (103 students), a veterinary institute (114 students), and an agricultural institute (109 stu dents). In the vicinity are the royal villa and stud-farm (horses and dromedaries) of San Rossore (the name is a corruption of Lussorio, see FORDUNGIANUS ) , and the mineral baths of San Giuliano, alkaline-ferruginous, with temperature 91.4° to 105.8° F. At the mouth of the Arno, joined to the city by a steam tram way (on the way is the old church of S. Piero in Grado) is the seaside resort of Marina di Pisa, also known as Bocca d'Arno, a well known centre for landscape painters. At Navacchio, 5 m. E. of Pisa, is a biscuit factory, 4 m. N. of which is Calci, and near it the large monastery of the Certosa di Pisa.