The Litani River, the classical Leontes, is an important water resource in southern Lebanon. The river rises in the fertile Beqaa Valley, west of Baalbek, and empties into the Mediterranean Sea north of Tyre. Exceeding 140 km in length, the Litani is the longest river in Lebanon and provides an average annual flow estimated at 920 million cubic meters. The waters of the Litani both originate and flow entirely within the borders of Lebanon. It provides a major source for water supply, irrigation and hydroelectricity both within Southern Lebanon, and the country as a whole.

The Beqaa Valley, also transliterated as Bekaa, Biqâ, and Becaa and known in classical antiquity as Coele-Syria, is a fertile valley in eastern Lebanon. It is Lebanon's most important farming region. Industry also flourishes in Beqaa, especially that related to agriculture.