The Incas and Machu Picchu

The Inca realm, centred on Cusco, stretches from present-day Ecuador to Chile and rests on roads tens of thousands of kilometres long, on suspension bridges and storehouses of provisions. Records are kept in the knotted cords of the quipu; writing in the usual sense there is none. The peasants owe labour on the fields and the building sites, and the harvest is redistributed through the state stores. Machu Picchu was built under the ruler Pachacuti as a country estate: terraces, mortarless masonry and water channels on a mountain ridge above the river Urubamba.