How Did the Ancient South Americans Construct Massive Walls?

I should add buildings as well, since some aspects of the techniques used range from Egypt to South America. The first is rock softening. Rock Softening Hiram Bingham roamed South America in the early 1900s and is credited with rediscovering Machu Picchu in 1911. He relates the following: The modern Peruvians are very fond of speculating as to the method which the Incas employed to make their stones fit so perfectly. One of the favourite stories is that the predecessors to the Incas knew of a plant whose juices rendered the surface of a block so soft that the marvellous fitting was accomplished by rubbing the stones together for a few moments with this magical plant juice! By the time the Incas came along, they had to use much smaller stones (as seen in the background). The original methods had been forgotten. Sacsayhuaman – Top Attraction in the City tour of Cusco Quarry at ancient Ollantaytambo In the Sacred Valley Of Peru, showing row of moulded stones ready to be split apart