The Agricultural AreaThe agricultural area is a succession of terraces of different types and dimensions that most probably fulfilled two functions: agriculture, and land retention.
The structure of the terraces is composed of an outer wall of stone and a landfill of different levels: large stones, small stones, gravel, mud, and earth. These different strata facilitate drainage and avoid the accumulation of water. This type of construction has enabled agriculture upon these terraces until the beginning of the twentieth century.
Further terraces of lesser width are located on the lower reaches of Machu Picchu, all around the town. In this instance their function was not agricultural, but simply of land retention, to avoid erosion due to rainfall.
In the agricultural area there are five large buildings. These were used as colcas, or storage areas belonging to the Inca.