The canyon is called the Rhumel Gorge. It is so deep that the river running through the bottom looks tiny from above. Houses sit right at the edge of the cliffs, and from a balcony you can sometimes see eagles flying below you instead of above.
There are seven main bridges. The most famous is the Sidi M'Cid suspension bridge - when it was built in 1912, it was the highest bridge in the world. Walking across it feels like walking across the sky. Wind moves through the cables and the whole bridge gently sways.
Constantine has been a city for around 2,500 years. It is one of the oldest continuously lived-in places in the world. People built here because the cliffs made it easy to defend - you can only get up the hill from a few directions.
The city is also famous for its music. A special kind of slow, beautiful Algerian music called 'malouf' was developed here. Music shops, caf茅s and old streets full of tiled buildings still fill the old town. Constantine has been called Algeria's 'City of Music' as well as the 'City of Bridges'.