vThe area around Tiwanaku may have been inhabited as early as 1500 BC as a small agriculturally based village. Most research, though, is based around the Tiwanaku IV and V periods between AD 300 and AD 1000, during which Tiwanaku grew significantly in power. During the time period between 300 BC and AD 300 Tiwanaku is thought to have been a moral and cosmological center to which many people made pilgrimages. The ideas of cosmological prestige are the precursors to Tiwanaku's powerful empire.
Tiwanaku's location between the lake and dry highlands provided key resources of fish, wild birds, plants, and herding grounds for camelidae, particularly llamas. The Titicaca Basin is the most productive environment in the area with predictable and abundant rainfall, which the Tiwanaku culture learned to harness and use in their farming. As one goes further east, the Altiplano is an area of very dry arid land. The high altitude Titicaca Basin required the development of a distinctive farming technique known as "flooded-raised field" agriculture (suka kollus). They comprised a significant percentage of the agriculture in the region, along with irrigated fields, pasture, terraced fields and qochas (artificial ponds) farming. Artificially raised planting mounds are separated by shallow canals filled with water. The canals supply moisture for growing crops, but they also absorb heat from solar radiation during the day. This heat is gradually emitted during the bitterly cold nights that often produce frost, endemic to the region, providing thermal insulation. Traces of landscape management were also found in the Llanos de Moxos region (Amazonian food plains of the Moxos). Over time, the canals also were used to farm edible fish, and the resulting canal sludge was dredged for fertilizer. The fields grew to cover nearly the entire surface of the lake and although they were not uniform in size or shape, all had the same primary function.
Though labor-intensive suka kollus produce impressive yields. While traditional agriculture in the region typically yields 2.4 metric tons of potatoes per hectare, and modern agriculture (with artificial fertilizers and pesticides) yields about 14.5 metric tons per hectare, suka kollu agriculture yields an average of 21 tons per hectare.
Significantly, the experimental fields recreated in the 1980s by University of Chicago's Alan Kolata and Oswaldo Rivera suffered only a 10% decrease in production following a 1988 freeze that killed 70-90% of the rest of the region's production. This kind of protection against killing frosts in an agrarian civilization is an invaluable asset. For these reasons, the importance of suka kollus cannot be overstated.
As the population grew occupational niches were created where each member of the society knew how to do their job and relied on the elites of the empire to provide all of the commoners with all the resources that would fulfill their needs. Some occupations include agriculturists, herders, pastoralists, etc. Along with this separation of occupations, there was also a hierarchal stratification within the empire. The elites of Tiwanaku lived inside four walls that were surrounded by a moat. This moat, some believe, was to create the image of a sacred island. Inside the walls there were many images of human origin that only the elites were privileged to, despite the fact that images represent the beginning of all humans not only the elite. Commoners may have only ever entered this structure for ceremonial purposes since it was home to the holiest of shrines.

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