The valley, running generally west to east, is understood to include everything along the Urubamba River between the town and Inca ruins at Písac and Machu Picchu, 100 kilometres (62 mi) distant.
[7] The Incas built extensive irrigation works throughout the valley to counter deficiencies and seasonality in precipitation.
[9] By conquest or diplomacy, during the period 1000 to 1400 CE, the Inca achieved administrative control over the various ethnic groups living in or near the Sacred Valley.
[10] The attraction of the Sacred Valley to the Inca, in addition to its proximity to Cusco, was probably that it was lower in elevation and therefore warmer than any other nearby area.
In times of warfare, the Incas would take the decapitated skulls of their enemies and turn them into drinking vessels for chicha.
This ceremonial process of drinking chicha from the head of a foe symbolized the successful transformation from the disorder of warfare to the order of the Incan Empire.
[12] Large scale maize production in the Sacred Valley was apparently facilitated by varieties bred in nearby Moray, either a governmental crop laboratory[13] or a seedling nursery of the Incas.
[19] Oral histories in the Quechua language suggest that the ancient Inca married Pachamama (Mother Earth) and produced human offspring.
Machu Picchu, located in the Sacred Valley, is an example of the Incas adapting building strategies that acknowledge the topography of the area.