The Great Mosque at Djenne' is the largest adobe building in the world. Located in western Mali, the original mosque was built in the 13th century, but was demolished in 1834. It was the center of one of the most important Islamic learning centers in the world. Thousands of Islamic students came to Djenne' from all over west Africa to study the religion. The city of Djenne is considered the oldest city in sub-saharan Africa.
The current structure was completed in 1907. The mosque is one of the most important landmarks in all of Africa and the residents of Djenne participate in its maintenance during a unique annual festival. It was declared a UNESCO World Heritage Site in 1988.