Inca Terracing System Perfected

1473

Inca engineers refined the agricultural terrace system called andenes that carved the steep Andean mountainsides into productive stepped fields stretching from valley floor to cloud forest. Sophisticated irrigation channels diverted glacial snowmelt through terraces growing maize, potatoes, and quinoa at altitudes where no other civilization on earth attempted agriculture. The system fed an empire of perhaps twelve million subjects and still functions in parts of highland Peru and Bolivia today.