Ahaggar, also spelled Hoggar, is a large plateau in the north centre of the Sahara, southern Algeria, along the Tropic of Cancer, North Africa. Its height is above 3,000 feet (900 m). The mountains cover an area of approximately 550,000 square km (212,000 square miles).

The plateau, about 965 miles (1,550 km) north to south and 1,300 miles (2,100 km) east to west, is a rocky desert composed of black volcanic (basalt) necks and of flows rising above a pink granite massif.

The Ahaggar Mountains in the southern Sahara rise to majestic summits; the tallest, Mount Tahat, reaches an elevation of 9,573 feet (2,918 metres) and is the highest peak in the country.

Prehistoric settlement is evident from extant rock paintings dating to 6000 BC.

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