megalithic stone fence was constructed around the enclosed settlement site of Kochio. Senegambia Between 1350 BCE and 1500/1600 CE, Senegambian megaliths (e.g., tumuli) were constructed for the purpose of ancestral reverence. At Wanar, Senegal, megalithic monolith-circles and tumuli (1300/1100 BCE – 1400/1500 CE) were constructed by West Africans who had a complex hierarchical society. In the mid-region of the Senegal River Valley, the Serer people may have created tumuli (before 13th century CE), shell middens (7th century CE – 13th century CE) in the central-west region, and shell middens (200 BCE – Present) in the southern region. The funerary tumuli-building tradition of West Africa was widespread and a regular practice amid 1st millennium CE. More than ten thousand large funerary tumuli exist in Senegal. Eastern Africa Ethiopia In the Ethiopian Highlands of Harar, the earliest construction of megaliths occurred. From this region and its megalith-building tradition (e.g., dolmens, tumuli with burial chambers organized in cemeteries), the subsequent traditions in other areas of Ethiopia likely developed. In the late 1st millennium BCE, the urban civilization of Axum developed a megalithic stelae-building tradition, which commemorated Axumite royalty and elites, that persisted until the Christian period of Axum. In the Sidamo Province, the megalithic monoliths of the stelae-building cultural tradition were utilized as tombstones in cemeteries (e.g., Arussi, Konso, Sedene, Tiya, Tuto Felo), and have engraved anthropomorphic features (e.g., swords, masks), phallic form, and some of that served as markers of territory. Sidamo Province has the most megaliths in Ethiopia. Aksumite Aksumite architecture flourished in the Ethiopian region, as attested by the numerous Aksumite influences in and around the medieval churches of Lalibela, where stelae (hawilts) and, later, entire churches were carved out of single blocks of rock. Other monumental structures include massive underground tombs often located beneath stelae. Other well-known structures employing monolithic construction include the Tomb of the False Door, and the tombs of Kaleb and Gebre Mesqel in Axum. Most structures, however—such as palaces, villas, commoner's houses, and other churches and monasteries—were built of alternating layers of stone and wood. Some examples of this style had whitewashed exteriors and/or interiors, such as the medieval 12th-century monastery of Yemrehanna Krestos, which was built in Aksumite style. Contemporary houses were one-room stone structures, two-storey square houses, or roundhouses of sandstone with basalt foundations. Villas were generally two-to-four storeys tall and had sprawling rectangular plans (cf. Dungur ruins). A good example of still-standing