The Ollantaytambo Sanctuary- a preserved site where the Inca people had a large city. The Incans were incredible engineers, crafting together rocks, weighing tons, so tightly that you could not slip a piece of paper between them. The boulders were drawn from mountain passes very far away, across rivers and mountain passes. It reportedly took 10,000 craftsmen and support staff to build Ollantaytambo.
Peru
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