Constantine قسنطينة

Constantine is situated on a plateau at 640 meters (2,100 ft) above sea level. The city is framed by a deep ravine and has a dramatic appearance. The city is very picturesque with a number of bridges over Rhumel river and a viaduct crossing the ravine. The ravine is crossed by four bridges, including Pont Sidi M'Cid. Constantine is the rail head of a prosperous and diverse agricultural area. It is also a center of the grain trade and has flour mills, a tractor factory, and industries producing textiles, wool, linen and leather goods. Algeria and Tunisia serve as its markets.

Source:

http://en.wikipedia.org/wiki/Constantine,_Algeria

Constantine is located in north-eastern Algeria 80 km from the Mediterranean coast. This is a historic city and an exceptional due to its construction on a rock.
This old ancient city of Algeria, capital of the prefecture, is a city of war steep and inaccessible. Sitting on a single rock over 600 meters, including sections cut perpendicularly to an immense height and the feet which Rhumel flowing and Bou Mezroug this site as an irregular quadrangle, arranged amphitheater. It is affordable by only one side, the plateau Koudiat Aty, which is separated from the city by the wall and is the real point of attack. The wall opens several doors, one of which is easily accessible but protected by strong fortifications. On the north side, called Mansura, the city is only accessible by a Roman bridge 5 m wide, laid on both sides of the cutoff Rhumel. It is closed by a double door arranged in a gallery right angle is called the door of El Kantara. Apart from these two points, the city is absolutely inaccessible. The various troops who occupied the city are stationed on a high point north of the city: the kasbah.
situation.

Source: http://www.apc-constantine.gov.dz/