river, west-central Lebanon, flowing westward and emptying into the Mediterranean Sea north of Beirut. Apart from a small section near the coast the river is seasonal; in summer its only source is a spring at the Jʿītā Cave. The river is about 19 miles (30 km) in length.

The ravine through which the Kalb River flows was inhabited as early as Paleolithic times. Inscriptions commissioned by Nebuchadrezzar II (c. 630–562 BC), king of the Chaldean (Neo-Babylonian) empire, are found on the right bank of the river. Other historical inscriptions, also commemorating the victories of their authors, were carved on stelae on the left bank of the river. These include inscriptions made for Ramses II the Great (1290–1224 BC), in hieroglyphics; King Esarhaddon (680–669 BC), in Assyrian; Emperor Marcus Aurelius (AD 211–217), in Latin; and az-Zahir Sayf ad-Din Barquq (1382–1399), in Arabic. There are also commentaries in French and English on affairs of the region as recent as 1946.

Agriculture along the river consists of citrus fruit and bananas grown on the coastal plain; grapes, olives, and grains raised on the highland slopes; and figs, vegetables, and grains cultivated in the higher part of the river valley. The major town along the river is Biskintā.