Machu Picchu: 100 Years Since Its Rediscovery

Walls
The central buildings of Machu Picchu use the classical Inca architectural style of polished dry-stone walls. The Inca were masters of the ashlar technique, in which blocks of stone are cut to fit together tightly without mortar. Many junctions in the central city are so well constructed that not even a blade of grass will fit between the stones.

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