river in eastern Afghanistan and northwestern Pakistan, 435 miles (700 km) long, of which 350 miles are in Afghanistan. Rising in the Sanglākh Range 45 miles west of Kabul city, it flows east past Kabul and Jalālābād, north of the Khyber Pass into Pakistan, and past Peshāwar; it joins the Indus River northwest of Islāmābād. The river has four major tributaries, the Lowgar, the Panjshēr, the Konar (Kunar), and the Alīngār.

Much of the Kābul's course is tapped for irrigation, so much so that west of Kabul city the river often dries up in summer. Irrigation is also extensive in the Jalālābād and Peshāwar areas. A few miles below the junction with the Panjshēr, a hydroelectric plant has been built. The Kābul River valley is a natural route for travel between Afghanistan and Pakistan; the Macedonian Alexander the Great used it to invade India in the 4th century BC. Since 1945 the Peshāwar-Jalālābād-Kabul Highway has occupied the valley. The river is navigable by flat-bottomed vessels below Kabul city.