Probably the most historically and architecturally interesting city in all of Mali is Djenne. The city served as an important element of the trans-Saharan gold trade, and it is still a regional hub thanks to its impressive weekly market that gathers residents from all the surrounding areas. By far the most amazing landmark in the city, however, is the Great Mosque, which is the largest mud brick building in the world. The Islamic Mosque dates back to the 13th century, although it wasn’t officially completed until 1907.