In what country would you find the largest mud brick building in the world?

The Great Mosque of Djenné is a UNESCO (The United Nations Educational, Scientific and Cultural Organization) World Heritage site. It is located in Africa near the geographic center of landlocked Mali. The Great Mosque of Djenné is the World's Largest Mud-Brick Structure. Inhabited since 250 B.C., Djenné became a market center and an important link in the trans-Saharan gold trade. In the 15th and 16th centuries, it was one of the centers for the propagation of Islam. Its traditional houses, of which nearly 2,000 have survived, are built on hillocks (toguere) as protection from the seasonal Niger river floods. West Africa is home to a collection of incredible mud-brick mosques.

It was built in 1907, but the town's mud architecture dates back to at least the 14th century. To create the buildings, masons pack mud and straw into bricks, allow them to dry in the sun, and stack them to form walls. The walls are ornamented with palm tree sticks known as “toron”. The mosque’s platform measures about 75 meters wide and it is about three meters high. The entry to the mosque is from the northern side.

Though the buildings are sturdy and often sprawling—the Great Mosque can hold 3,000 worshippers—they are still vulnerable to the elements. Rain, humidity, and temperature changes cause cracks and erosion in the walls. Djenne's mud masons regularly band together and repair the mosque to keep it from falling apart.