Some of them date back to the 13th century. Researchers believe there are many thousands more under the sands of the Sahara. Among them are textbooks on mathematics and astronomy, as well as writings on social and economic life in the region during the Golden Age. At the time, Timbuktu was an academic center with 25,000 students.
Because of its illustrious history, it was inscribed on the UNESCO World Heritage List in 1988.
