Encyclopædia Britannica, Ninth Edition/Tortona
TORTONA, a town of Italy, in the province of Alessandria, on the right bank of the Scrivia, at the northern foot of the Apennines, 13 miles to the east of Alessandria, was formerly a place of strength until its fortifications were destroyed by the French after Mareugo (1799); the ramparts are now turned into shady promenades. The cathedral, erected by Philip II., is architecturally uninteresting, but contains a remarkably fine Roman sarcophagus. Silk-weaving, tanning, and hat-making are the chief industries; and there is some trade in wine and grain. The population in 1881 was 9023 (commune 14,442).
Dertona is spoken of by Strabo as one of the most important towns of Liguria, and is alluded to by Pliny as a Roman colony. In the Middle Ages it was zealously attached to the Guelphic cause, on which account it was twice laid waste by Frederick Barbarossa (in 1155 and 1163).