Waru-waru, or camellones, were raised planting platforms flanked by water-filled canals built across the cold, flood-prone altiplano around Lake Titicaca. The canals stored daytime heat and released it at night, buffering crops against the frosts that limit farming above 3,800 metres, while also draining waterlogged ground and trapping nutrient-rich sediment. The system reached vast extent under the Tiwanaku polity in the first millennium CE before largely falling out of use. Experimental revival projects have since reconstructed working fields in Peru and Bolivia.
It shows sophisticated micro-climate and water engineering sustaining one of the highest farmed landscapes on Earth and underpinning the Tiwanaku state. The raised-field grid shaped the settlement pattern of the southern altiplano.