Djelfa is the capital city of Djelfa province, Algeria. It has a population of 154,265 (1998 census). The city lies at the junction of the N1 and the N46. A pleasant medium-size city, north-central Algeria, in the Ouled Nail Mountains at an elevation of 3,734 feet (1,138 m). It is situated between the towns of Bou Saâda and Laghouat. Djelfa town is at a point of transition between the dry, steppelike High Plateaus of the north, with their chotts (intermittent salt lakes), and the Sahara (south). The town was founded in 1852 as a French military post on a geometric plan. It serves as an important livestock market centre for the seminomadic Ouled Nail confederation. Djelfa is on the 12,000 mile Africa Trail. Neolithicart in Djelfa The surrounding region for centuries has been the meeting place of the Ouled Nail, who live in black-and-red striped tents and claim descent from the Prophet Muhammad. The area is notable for its abundance of Neolithic rock carvings dating from 7000 to 5000 BC. North of Djelfa town there is an imposing physical feature known as Salt Rock (Rocher de Sel) that resulted from the erosion of rock salts and marls by rain, and to the west of the town Megalithic funerary structures are found. See separate article, Rock art of the Djelfa region. During Philippe Pétain's period, a concentration camp was placed in Djelfa. Djelfa has a semi-arid climate (Köppen climate classification BSk), with hot, fairly dry summers and cool, somewhat moist winters. Snow is not unusual in winter. (Arabic) Djelfa Forums (French) Djelfa - The capital of the Algerian Highlands.