Large Neolithic proto-urban walled stone settlements, likely built by Mande-speaking Soninke peoples date from around 1,600-400 BC at Dhar Tichitt and nearby sites in southeastern Mauritania.[5] The first Great Mosque of Djenné (built around 1200 to 1330[6]) in modern Mali, according to traditional accounts, was constructed on the site of an older pre-Islamic palace by the city's king.[7] Starting in the 9th century AD, Muslim merchants came to play a vital role in the western Sahel region through trans-Saharan trade networks.[9] Here, a mosque has been discovered which consisted of a courtyard, a prayer hall, and a square minaret, built in dry stone covered in red mud used as plaster.[15] Under Songhai influence, minarets took on a more pyramidal appearance and became stepped or tiered on three levels, as exemplified by the tower of the mosque–tomb of Askia al-Hajj Muhammad in Gao (present-day Mali).In the southern Sahel and savannah regions mudbrick and rammed earth are the main material and is now associated with the most monumental examples of West African Islamic architecture.They have tapering buttresses with cone-shaped summits, mosques have a large tower over the mihrab, and wooden stakes (toron) are often embedded in the walls – used for scaffolding but possibly also for some symbolic purpose.[19] The traditional earth building construction technology has a particular name called “banco” in West Africa, meaning a wet-mud process similar with the concept of coil pottery.In 2021, 8 small mosques in northern Côte d’Ivoire exemplifying a special type of Volta Basin religious architecture were also inscribed on the World Heritage list.