I. A province of Italy, in Tuscany; area, 1,276 sq. m.; pop. in 1872, 239,901. It is watered by the Arno, and includes the valley of the Chiana, 20 m. long, formerly a vast and pestilential marsh, but which has been drained within the last century and converted into about 40 sq. m. of the most fertile land of Italy and perhaps of Europe. Arezzo is famous for its wines, corn, oil, and fruits. Among the towns of this province are Cortona and Monte-pulciano.

II. A city (anc. Arretium or Are-tium), capital of the preceding province, situated in a fertile valley, near the confluence of the Chiana and Arno, about 30 m. S. E. of Florence; pop. 38,907. In antiquity it was one of the principal states of Etruria. Its extensive walls are undoubtedly Etruscan, and were of importance to the Romans as a barrier against the Cisalpine Gauls. It was celebrated for its terra-cotta vases, ranked by Pliny with those.of Samos and Saguntum. During the contest of the Guelphs and Ghibel-lines, Arezzo, then a very populous city, fought against Florence, but was finally obliged to yield. Among the public buildings are the magnificent Loggie, by Vasari, the cathedral and several beautiful churches, the Museo Bacci, and the Palazzo Publico, which has upon its front a curious series of the armorial bearings of the successive podestas, amounting to several hundreds. It is the birthplace of a number of distinguished men, hence known by the surname of Aretino, as well as of Petrarch, Vasari, and others.