Two things sit in the Nyanga uplands and they are usually run together. One is an archaeological landscape. The other is a mountain with rules that are enforced now.
The terraces. The Nyanga uplands carry one of the largest terraced agricultural landscapes in Africa: stone-faced terraces, water furrows running for kilometres, and thousands of stone-lined pit structures, built between roughly the fifteenth and nineteenth centuries by farming communities working the hillsides intensively.
The misreading. Early settler writers called the pits slave pits and read the whole landscape as the work of some earlier, foreign, more capable people who had since vanished. Excavation established that the pits were byres for small livestock (sunk, walled, with a covered entrance passage, to protect goats and sheep from predators and cold at altitude), and that the builders were the ancestors of the people farming there when Europeans arrived.
This is the same reflex that produced the Great Zimbabwe theories, running on the same ground and in the same decades: sophisticated construction encountered in southern Africa, attributed to anyone but the people who built it, with a story about foreign origin doing the work. It is worth recording as a pattern rather than as a single famous error, because the pattern is what made the Great Zimbabwe campaign possible.
The mountain is a separate matter and it is not archaeology. Mount Nyangani is the highest point in Zimbabwe and is sacred to Manyika communities. The prohibitions around it are specific, current, and locally enforced: visitors should be led by someone who knows the mountain, should not point at features, should not take anything away, and should not speak carelessly on it. People who disregard them are held to be at risk.
The mountain has a long record of walkers going missing, and national park staff have mounted searches more than once. Local elders attribute the disappearances to breaches of the prohibitions. This entry reports that as what it is, the account given by the people whose mountain it is, and the reason the rules are taken seriously locally, without adjudicating it, and notes that the prohibitions are in force whatever an outsider concludes about the cause.
The distinction matters for how the two halves are treated. The terraces are a closed historical question that was answered. The mountain is not a historical question at all.