Andén

The benefits of andenes include utilizing steep slopes for agriculture, reducing the threat of freezes, increasing exposure to sunshine, controlling erosion, improving absorption of water, and aerating the soil.

[3] Agricultural terraces have been built and used by farmers around the world for thousands of years, mainly for the purpose of permitting cultivation on steep hillsides.

Archaeologists estimate that andenes covered about 1,000,000 hectares (2,500,000 acres) of land[5] and contributed substantially to feeding the approximately ten million people ruled by the Incas.

[6][a] The Spanish conquest of Peru in 1533 led to a demographic collapse in the Andes, as the Indigenous population precipitously declined due to European diseases and war.

"[9] At prestigious or royal sites, such as Machu Picchu, finely cut stone was used as the outer (visible) face of the retaining wall.

[11] In arid areas, such as the Colca Valley, where Andenes are still cultivated, water for irrigation is brought down from the snow melt of high peaks and springs via a complex system of canals and reservoirs.

[12] As strategies of risk management, farmers in the present day – and probably in pre-Columbian times – have up to 30 plots of land at different locations and grow a wide variety of crops.

[13] The stone retaining walls of andenes absorbed the sun's heat during the day and radiated it at night, warming the soil and preventing damage to frost-sensitive crops such as maize.

[5] In 2014, the Peruvian Ministry of Agriculture and the Inter-American Development Bank began a project to rehabilitate andenes, including those near Laraos in the Lima region.

[17] The andenes possess an appeal beyond the historical and their original economic motivations: they are also landscape resources whose situation in the Andes Mountains has notable aesthetic value.