Djingarey Ber, 'the Great Mosque', is Timbuktu's oldest monument and its major landmark. Located at the western corner of the old town, the mosque is almost entirely built in banco (raw earth), which is used for mud bricks and rendering. The exceptions are the northern wall, reinforced in the 1960s in alhore (limestone blocks, also widely used in the rest of the town), and the minaret, also built in limestone and rendered with mud. The mosque's maintenance, consisting mainly of repairing the mud rendering, is regularly undertaken upon appeal by the imam to the population, whose contributions take the form of money, materials and labour.
The town of Timbuktu and its monuments were included in UNESCO's World Heritage List in 1988, and in 1989 the three mosques of Djingareyber, Sankoré and Sidi Yahia were included in the List of World Heritage Monuments in Danger. As a result, in 1996 the World Heritage Centre financed an operation for the emergency restoration of these mosques. In December of that year, the architects of the GAIA Project (ICCROM/CRATerre-EAG) put together a training programme, which actively involved not only local committees and experts in indigenous techniques but also the population itself.
The mosque of Djingareyber is the oldest, largest and most complex of the three mosques. The intervention was crucial to prevent a process of decay. These works cannot be entirely separated from the work done in the other two mosques, yet its added symbolic value is indisputable. The restoration of a building of this type, however, is a continuous process. After the intervention of 1996, minor repairs and maintenance have been regularly carried out, the most important being the consolidation and rendering of the minaret in 2000. It is evident, however, that the mosque will soon need to enter another phase of structural restoration.
The foundations are made of stone. Otherwise the materials and construction methods are very similar to those at Djenné. Load-bearing elements are generally in mud brick with wooden tie-beams laid at intervals at the courses. Reinforcing layers of alhore stone have been added at various times to walls, buttresses, parapets and the minaret. Roofs are made of palm-tree joists crossed with branches and covered first with palm matting and then fine mud. The branches are left exposed in some parts of the ceiling and rendered in mud in others, probably reflecting different periods of maintenance work.