The river Ticino (Lombard: Tisín; German: Tessin; Latin: Ticinus) is the most important perennial left-bank tributary of the Po River. It has given its name to the Swiss canton through which its upper portion flows.
The river rises in the Val Bedretto in Switzerland at the frontier between the cantons of Valais and Ticino, is fed by the glaciers of the Alps and later flows through Lake Maggiore, before entering Italy. The Ticino joins the Po a few kilometres downstream (along the Ticino) from Pavia. It is about 248 kilometres (154 mi) long. The highest point of the drainage basin is the summit of Grenzgipfel (a subpeak of Monte Rosa), at 4,618 metres (15,151 ft). Beneath it flows the Anza River, a right-bank tributary of the Ticino.
The river is dammed in Switzerland in order to create hydroelectricity, while in Italy it is primarily used for irrigation.
The legendary Gallic leader Bellovesus was said to have defeated the Etruscans here in circa 600 BC. Ticino was the location of the Battle of Ticinus, the first battle of the Second Punic War fought between the Carthaginian forces of Hannibal and the Romans under Publius Cornelius Scipio in November 218 BC. The Ticino was in the territory of the Duchy of Milan during much of the later medieval and early modern period, although its upper portion as far as Bellinzona in 1500 and as far as the shores of Lago Maggiore in 1513, fell to the Swiss as a result of their campaigns in the Italian Wars.