Every spring, the entire population of a Malian city picks up baskets of mud and climbs scaffolding to replaster their mosque by hand. The building is the Great Mosque of Djenné, the largest mud-brick structure in the world, and the ritual of remaking it has gone on for generations. There is no better introduction to Djenné than this: a place where the most monumental thing ever built is also the most fragile, kept standing only because the people who love it rebuild it again and again.
Rising from a raised platform above the floodplain, the Great Mosque is built entirely of sun-dried mud brick, its walls bristling with palm-wood beams that jut from the surface like spines. Those beams are not ornament. They are permanent scaffolding, the handholds and footings for the annual replastering, the crépissage, when the whole city turns out to smear a fresh skin of mud over the building before the rains can dissolve it. The current mosque was completed in 1907 on the site of a far older one, and its three towers and ranks of pinnacles have become the defining image of West African architecture. Walk the streets around it slowly, on foot; the city is a museum of mud, every house shaped by the same hands and the same earth.
Djenné's fame as a market town is older than the mosque, older than Islam in the region, older than almost any city in sub-Saharan Africa. Just a couple of kilometers from the modern town lie the mounds of Djenné-Djeno, an ancient city that flourished from around 250 BCE and was a thriving urban center long before the empires of Mali and Songhai rose around it. UNESCO recognized Djenné and its ancient predecessor as a World Heritage Site, noting that Djenné 'became a market centre and an important link in the trans-Saharan gold trade.' To stand here is to stand at one of the oldest continuous experiments in city life that Africa, or the world, has to offer.
Time your visit for Monday. That is when Djenné becomes itself: minibuses and bush taxis pour in from across the region, and the great square in front of the mosque fills with one of the most photographed markets in Africa, a churning sea of color, cloth, livestock, and trade beneath those towering mud walls. On other days the town is quieter, and reaching it takes patience, often a ride to the Djenné junction on the main Bamako-Mopti road and a wait for onward transport. When the river runs high you can take a pinasse, a long wooden boat, out to the Fula villages nearby, gliding across delta waters the same way traders have moved goods here for more than a thousand years.
Djenné sits at roughly 13.90°N, 4.55°W in central Mali, on an island in the floodplain where the Bani River joins the inland Niger delta. From the air the Great Mosque dominates the old town, and in flood season the city stands ringed by shining water, reached by causeway and ferry. Nearest airports: Mopti / Ambodédjo (GAMB) to the northeast is the regional gateway; Bamako-Sénou (GABS) is the main international airport, far to the southwest. Recommended viewing altitude 3,000-5,000 ft AGL for the town and mosque. The delta is most dramatic just after the floods, roughly December through April; the wet season turns the surrounding plain into open water.