One of the two historic mosques of Timbuktu (the other being the Jingereber), the Sankore Mosque was built during the declining years of the Empire of Mali, in the early 15th century A.D. Architecturally, it is remarkable for its large pyramidal mihrab. But this is not its real claim to fame -- indeed, it is smaller and less intricate than earlier Malian mosques including the 13th century mosque of Djenne. Instead, it is famous for being the center of the great Islamic scholarly community at Timbuktu during the 16th century A.D.
The medieval "University of Timbuktu," often referred to as the "University of Sankore" was very different in organization to the universities of medieval Europe. It had no central administration, student registers, or prescribed courses of study; rather, it was composed of several entirely independent schools or colleges, each run by a single master or imam. Students associated themselves with a single teacher, and courses took place in the open courtyards of mosque complexes or private residences. The primary focus of these schools was the teaching of the Koran, although broader instruction in fields such as logic, astronomy, and history also took place.
As anyone who wished could establish one of these colleges, standards amongst them are said to have been very uneven. However the imams of the Sankore mosque are known to have been the most respected. The university was adversely affected by the Moroccan invasion of the 1590s and the deportation of its best scholars. It never again regained its 16th century eminence.