The Great Mosque of Djenne is the largest mud brick or adobe building in the world and is considered by many architects to be the greatest achievement of the Sudano Sahelian architectural style, albeit with definite Islamic influences.

The mosque is located in the city of Djenne, Mali on the flood plain of the Bani River. The first mosque on the site was built in the 13th century, but the current structure dates from 1907. As well as being the centre of the community of Djenne, it is one of the most famous landmarks in Africa.

The entire community of Djenne takes an active role in the mosques maintenance via a unique annual festival. This includes music and food, but has the primary objective of repairing the damage inflicted on the mosque in the past year, mostly erosion caused by the annual rains and cracks caused by changes in temperature and humidity.

In the days leading up to the festival, the plaster is prepared in pits. It requires several days to cure but needs to be periodically stirred, a task usually falling to young boys who play in the mixture, thus stirring up the contents. Men climb onto the mosques built in scaffolding and ladders made of palm wood and smear the plaster over the face of the mosque.

Another group of men carries the plaster from the pits to the workmen on the mosque. A race is held at the beginning of the festival to see who will be the first to deliver the plaster to the mosque. Women and girls carry water to the pits before the festival and to the workmen on the mosque during it. Members of Djennes masons guild direct the work, while elderly members of the community, who have already participated in the festival many times, sit in a place of honour in the market square watching the proceedings.

The original mosque presided over one of the most important Islamic learning centres in Africa during the middle Ages.

The historic areas of Djenne, including the Great Mosque, were designated a World Heritage Site by UNESCO in 1988. While there are many mosques that are older than its current incarnation, the Great Mosque remains the most prominent symbol of both the city of Djenne and the nation of Mali.