At Chivay, the Colca River valley is wide enough to provide room for a town in which 5,000 people currently live. Before the Spanish arrived, many more people lived in the Colca Valley. Yanque, another village in the valley, now has a population of about 500; at one time it had a population of 17,000.
As the population grew, the Collagua and Cabana people needed to increase their agricultural production. Between 600 and 900 AD, a system of irrigated terraces was developed, and by the time the Spanish arrived, the valley was covered with terraced fields full of numerous varieties of potatoes, corn, beans and quinua.
As the population declined, many fields were no longer needed, and they were left to nature.
The Colca River valley and the town of Chivay
Looking West into Colca Canyon
The terraces from the valley perspective
Close-up of terraces
For more history of the canyon, see the local government’s site colcaperu.gob.pe (in English).