• Foto Number: KDI-231

The internal drainage system of the terraces of Machu Picchu, created by the Incas, consisted of three layers, a first layer of mulch, a second of sand and a third of gravel. These layers allowed the water sucked in by the terraces not to flood the terraces, but to run downhill and be quickly absorbed without creating landslides that would endanger the city and its inhabitants. - 1976

• Keywords:
  South America Peru Machu Picchu Incas Andenes Inca-Culture precolombian Archaeology ruin