In which country is the Bab El Kantra bridge located?

Bab El Kantra Bridge is one of eight famous high-level bridges that cross the Rhumel River gorge in Constantine, Algeria. The Kantara bridge is the oldest and has taken several different forms over the years: from a 1792 Ottoman-style multi-arch bridge, to an 1863 French iron arch, to its current form as a concrete arch bridge. Like the higher Sidi M'Cid Bridge, there is a unique, natural “bridge” almost directly under the span that blocks much of the river from view. Partial remains of the earlier stone bridges can still be seen on top of this natural bridge.

The bridge as we see it today, was erected in 1788 and 1789 under the principality of Salah Bey by a Balearic engineer. It has two levels. The lower level is made up of two arches; one of them, close to the city, was solidified at an unknown time. The two arches are supported by three piers whose structure is obviously Roman, from the base to the cornice. On the second level, which rises 16 meters above the lower floor, it is made up of four arches. The two central ones lean on the lower arches; its vaults are pointed, while the sides are circular vaults and visibly larger. The height of the bridge reaches 65 meters (213 ft); the board is 60 meters (196 ft) long.