The Arno is a river, the most important river of central Italy after the Tiber in the Tuscany region of Italy. The river originates in the Casentino area of the Apennines on Mount Falterona, turns near Arezzo to the west, has a very variable discharge. The mouth of the river was once near Pisa, crosses Florence. The river flood ed this city in 1966 in historical times. Recent years have alleviated greatly the problem in recent years. New conservation techniques were inspired by the disaster. Basin Authority of the Arno Tale decreto ai sensi dell.
Irtysh River is a river, the chief tributary of the Ob River