??They brought as much information as we need to know that the Algerian Sahara was one of the cradles of civilization.That made it open to many ancient civilizations which made of it one of the richest countries in terms of heritage sites as Tipaza, Djemila, Tassilin'Ajjer, Timgad, the M'zab Valley, and the Qalaa of Banu Hammad.Emir Bulughin had rebuilt the town into an important trading port called Al-Jaza'ir until then, Algiers had less influence on international commerce than the other Algerian maritime cities because it had fewer harbors.