Constantine is one of the major cities of eastern Algeria, not far from the Tunisian border. The setting is extraordinary: the Rhumel Gorge, a deep canyon carved through a limestone plateau, protects the old city on almost all sides, giving it a dramatic, nearly impregnable position that no amount of urban development has managed to diminish.
The gorge can be crossed by seven bridges and viaducts. The most famous is the Sidi M'Cid Bridge, a suspension bridge 175 metres above the river; the most imposing is the Sidi Rached Viaduct, a 107-metre stone arch structure that was the longest of its kind in the world when built in 1912. The gorge is unfortunately polluted, which is a shame given the spectacular natural setting, but the views from the bridges remain vertiginous and unforgettable.
The Ahmed Bey Palace is the finest Ottoman building in Algeria; the Cirta Museum covers the Roman city of Cirta that preceded Constantine; and the old medina rewards hours of wandering on its steep lanes along the gorge edge. The Emir Abdelkader Mosque in the new city is among the largest in the world. Constantine has a long tradition as a centre of learning and culture in the Maghreb — this is a city where people sit in cafés for hours talking philosophy and politics, and where conversation is one of the main attractions.