Inca Terrace Agriculture (Andean Terrace System)

Timeline

1. c. -500–1200Andean highlands (in present-day Peru and Bolivia) · BoliviaPre-Inca cultures (Pucara, Tiwanaku, and others) had already built rudimentary terraces in the Andean highlands, revetting slopes with stone or mixed earth and stone and pairing them with simple water-diversion channels, converting hillsides into platforms for growing maize, quinoa, and potatoes, and laying the technical foundation for the Inca Empire's large-scale promotion.
2. 1438–1493Core Inca region (around Cuzco and the Sacred Valley) · Cuzco RegionAfter Pachacuti's reign, the empire organized large labor forces to build terraces through the mit'a labor system, pairing them with precise stone-channel irrigation; representative works were built in the Cuzco Sacred Valley (Urubamba/Vilcanota Valley), Moray, and elsewhere. Terrace agriculture became the core support of the empire's food self-sufficiency and storage system.
3. 1511–1520Tawantinsuyu (the entire Andean mountain region) · Andean RegionDuring Huayna Capac's reign the terrace system continued to expand, with total area estimated at over a million hectares, covering present-day Peru, Ecuador, Bolivia, and northern Chile. Through precise slope control and microclimate use (terraces on south-facing and north-facing slopes could grow different crops), potatoes and quinoa were cultivated above 4,000 meters, providing the empire with stable food reserves.
4. 1533Andean regions of Peru and Bolivia · BoliviaAfter the Spanish conquest the mit'a system collapsed, the indigenous population plummeted through disease and exploitation, and many terraces lost maintenance and were abandoned; since the late 20th century, the Peruvian government and international organizations have promoted terrace restoration projects, reviving terrace agriculture in some areas, which is regarded as a traditional model of climate-adaptive agriculture.