Great Zimbabwe
Colonial-era authorities spent decades insisting Africans could not have built this city — so how, exactly, did a Shona state organize the labor, engineering skill, and long-distance trade needed to raise 800,000-plus mortarless granite blocks into walls eleven metres high, and why, after roughly two centuries at the height of its power, was the city abandoned?
c. 11th-15th century CE · Masvingo Province, Zimbabwe