Due to great development and expansion, the Inca state needed administrative centers for their socioeconomic organization.

In these administrative centers rites and ceremonies of reciprocity were celebrated and the harvests from the so-called Inca's lands and products made by the various ethnicities were stored. Reciprocity was, in effect, the main gears and the basis of the organization of a country that did not know the use of money. In the beginning of the Inca state the then curaca of Cuzco met in the plaza of Aucaypata with the neighboring lords and after celebrating their meeting with festivities and public meals, the Inca offered them gifts and exchanged women to create kinship ties. Only after this delivery the Inca expressed his "plea" to the lords so they would perform various communal labors with their people or provide soldiers for the army. The ethnic chiefs were dealt with using the same procedure to get them to annex to the State without the necessity of going to war.

The system made possible the rapid growth and expansion of Tahuantinsuyo, but at the same time it imparted a certain fragility to the bases because all the ethnic lords had to do was accept the "plea" of another personage to annul any former reciprocity agreement. With the development of the sovereign's power, the Inca could no longer meet with the curacas in Cuzco and for that reason he had to build places all across the country for representation of the Inca with the Andean authorities. The centers were characterized by having a main plaza of exceptional dimensions and for numerous warehouses for storing products.

Huanuco Pampa

Huanuco Pampa, place studied by Craig Morris, is the best and largest example of Inca administrative centers. The site covers an area of 2 square Km, it possesses between three thousand five hundred and four thousand visible structures and was built on virgin land during the first half of the fifteenth century.

Its main plaza measures five hundred fifty meters by three hundred fifty meters, an enormous extension with an imposing ushnu (small stone structure situated in the middle of the plaza which served as a throne for the Inca during certain ceremonies). Streets go out from the plaza, the most important being the trunk route which united Cuzco with Quito and the road divided the city into halves, Hanan-upper- and Hurin-lower. Another two streets subdivide the whole into four sectors or barrios and they were related with the typical fractionation of space, indispensable for the Inca organizational system.

A characteristic of the administrative centers is the high number of warehouses for the conservation of supplies not necessarily originating from the zone, but rather brought from places sometimes very distant. Numerous documents from archives coming from the central coast indicate that products were transported sometimes to Cuzco and sometimes to Huanuco Pampa, where there are more than two thousand warehouses.

Other centers

The majority of administrative centers were situated in the mountains along the main road which joined Cuzco with Quito.

In the south, Inca builders opted to take advantage of existing buildings limiting themselves to remodeling them. Places like the sanctuary of the Sun on the island of Lake Titicaca and that of the Moon on the island of Coata were important religious centers and they also served as administrative centers like the Chamber of the Day in Pachacamac.

On the Chinchaysuyu route, Vilcas Huaman-in the present province of Cangallo, Ayacucho-was an important center.

In Ecuador, Tumibamba was, at its beginning, only one of those centers. However, it acquired importance during the government of Huayna Capac who because he was born there, transformed it into a city, and embellished it. Outstanding was the temple of Mullu Cancha whose walls were covered with red Spondylus shells of high religious value.

On the central coast, the Sanctuary of Pachacamac was another administrative center and, farther south, Tambo Colorado; in Humay, Pisco was built for the same purpose, but unfortunately it has not been as thoroughly investigated by archaeologists as it deserves because of its state of conservation.