Still in Africa living in grass huts and eating roots and berries. They haven’t even thought of sea-faring voyages.
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Actually not - the west Africans along the Gold Coast were visited by the Portuguese in the mid-1600s. The Africans had running water, indoor plumbing, and very nice cities built entirely of wood. The amenities were left over from Roman times. They were very peaceful people and welcomed the Portuguese sailors.
Portugal at the time was the superpower and had the highest standard of living in Europe. The explorers begged the King to allow them to stay because the living conditions were so much better than in Portugal.
Alas, they were ordered to return home. The next incursion brought the beginning of European slave trade - slaves for firearms. The result was a competition to acquire slaves to sell.
This brought the end of the wooden west African civilization. Nothing remains now, as the jungle reclaimed all of it as the wood rotted and the vines and brush took over.
OK, OK. Sub-Saharan INTERIOR Africa.