Sustainability within a culture relies upon an organized infrastructure such that the populace is fed adequately, the diverse ethnic and social groups accept their societal responsibilities, and most importantly measures are taken to optimally use the available resources. The Inca Empire excelled in dealing with each of these concerns. Their storage and agricultural practices serve as examples of this success.

II. The Quollqas - Inca storage warehouses

A. Functions

Large and visible to locals and located in the center of the provinces were storehouses, called qollqas. Qollqas served as the functional warehouse of everyday goods as well as a physical reminder of the vast provisions offered by the empire in times of need (e.g. famine). Inca storehouses were purposely built in prominent locations where the local inhabitants of a region could see them. Such conspicuous placement served to impress the subject peoples as symbols of imperial might, displaying the resources controlled by the state. Because the people were also required to contribute labor (and ultimately goods) to the state, the storehouses also could have been constant reminders of their obligation to support the empire.

The Incas placed the qollqas at the tops of hills in order to:  

• be easily seen from all parts of the province-- as a constant psychological reminder of the state’s authority and surplus of goods
• avoid use of more arable lowlands
• take advantage of the wind and low temperatures of the high altitudes for its refrigerator like properties

The qollqa were normally designed with a rectangular or circular base. The rectangle was approximately 2.5-3.4 meters wide and 3-10m long. The circle base was approximately 5m in diameter. Qollqas were normally placed in a row on the top of a hillside. Respective to the size of the city, there could be anywhere from 2-15 qollqas.

• Surplus food
• Material goods
• Textiles
• Arms
• Coca leaves, cocaine -- mainly used in the religious rituals and by the elite
• Quinine -- an antimalarial drug accredited to Incan discovery

Although each village was responsible for being self-sufficient and contributing to the empire’s surplus, the few areas that were highly productive (well-irrigated coastal valleys) contributed a larger part to the surplus in Cuzco. This large movement of the surplus served as a tax mainly used to feed army members and state officials at state functions. As opposed to having a constant food source, one village’s surplus was moved around the empire.

Grains grown in the Peruvian highlands