Zimbabwe is dotted with stone ruins going back to the 11th century AD. Until the end of white-minority rule in 1980 (Rhodesia), these ruins were credited to Arabs or Phoenicians. My intuition is that there is a lot more (and a lot older) to be found here.
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Afric is all the sun’s, and as her earth
Her human clay is kindled; full of power
For good or evil, burning from its birth,
The Moorish blood partakes the planet’s hour,
And like the soil beneath it will bring forth:
Beauty and love were Haidée’s mother’s dower:
But her large dark eye show’d deep passion’s force,
Though sleeping, like a lion near a source.