PUNJAB PLAIN

large alluvial plain in northwestern India, having an area of about 38,300 square miles (99,200 square km) and covering the states of Punjab and Haryana and the union territory of Delhi except for the Shahdara zone. It is bounded by the Yamuna River on the east, the Shiwalik Hills on the north, the arid zone of Rajasthan on the south, and the Ravi and Sutlej rivers on the northwest and southwest, respectively. The plain, an area of early Aryan settlement, was, according to the Hindu epic the Mahabharata, the site of the epic war fought between the Pandavas and Kauravas. The Punjab Plain was ruled by ancient northern Hindu dynasties until the Muslims established firm control after the defeat of Prthviraja Cauhan by Muhammad Ghuri in AD 1192. The death of Aurangzeb in 1707 and the weakening of the Mughal rule at Delhi enabled the Sikh dynasty to seize power in the region. The Punjab Plain has considerable strategic importance, since its western boundary coincides with the India-Pakistan border. Its geologic origin is Tertiary (except in the extreme south), its surface having been built up by the silting action of meandering streams. The plain is slightly undulating, sloping from 2,140 feet (650 m) in the northeast to 700 feet (200 m) in the southeast. The Ravi, Beas, Sutlej, and Yamuna are perennial rivers. Tropical thorn forests grow in the southeast, and tropical dry deciduous forests are found in the submontane region in the north. Agriculture is the mainstay of the region's economy, and most of the plain is farmed; cereals, cotton, sugarcane, and oilseeds are grown. Most of the region is crisscrossed by irrigation canals. Large-scale industries centred in New Delhi, Amritsar, Ludhiana, Jullunder, and Chandigarh produce textiles, bicycle parts, machine tools, agricultural implements, sporting goods, rosin, turpentine, and varnish.