and daub, lie around a courtyard. Animal designs mark the walls, and palm leaves cut to a tiered shape provide the roof. Mali At Tondidarou, in the Malian Lakes Region, there are megaliths of an anthropomorphic nature (e.g., face, navel, scarifications) that date between 600 CE and 700 CE. At the Inner Niger Delta, in the Mali Lakes Region, there are two monumental tumuli constructed in the time period of the Trans-Saharan trade for the Sahelian kingdoms of West Africa. The El Oualadji monumental tumulus, which dates between 1030 CE and 1220 CE and has two human remains buried with horse remains and various items (e.g., horse harnesses, horse trappings with plaques and bells, bracelets, rings, beads, iron items), may have been, as highlighted by al-Bakri, the royal burial site of a king from the Ghana Empire. The Koï Gourrey monumental tumulus, which may date prior to 1326 CE and has over twenty human remains that were buried with various items (e.g., iron accessories, an abundant amount of copper bracelets, anklets and beads, an abundant amount of broken, but whole pottery, another set of distinct, intact, glazed pottery, a wooden-beaded bone necklace, a bird figurine, a lizard figurine, a crocodile figurine), and is situated within the Mali Empire. Nigeria Several societies in pre-colonial Nigeria built structures from earth and stone. In general, these structures were primarily defensive, repelling invaders from other tribes, but many settlements put spiritual elements into their construction. These defensive structures were primarily constructed from earth, occasionally plastered. Dump ramparts consist of an outer ditch and inner bank and can span from 1/2 meter to 20 meters across in the largest settlements such as Benin and Sungbo's Eredo. Coursed mud walls in the Guinea and Sudan savannas were laid in layers of mud. Each layer of mud would be held in place by wooden framing, allowed to dry, and built on top of. At the most significant settlement in Koso, these walls averaged 6 meters in height, tapering from 2 meters thick at the base to 1/2 meter thick at the top. Tubali walls in northern Nigeria have two components: sun-dried mud bricks held together with mud mortar. Walls in this style have a tendency to deteriorate in wetter climates. These mud constructions were usually plastered with mud mixed with other materials. The defensive purpose of this was to create a smoother, unscalable surface to help repel