Cuzco, the "Navel of the Earth"
The Inca Empire was governed smoothly and efficiently from Cuzco. Rebuilt during the reign of Pachacuti in the shape of a crouching puma (mountain lion), Cuzco was designed to symbolize strength and power. Only the highest nobles and priests were allowed to live there.
Keeping Government Records
The Incas used quipu to keep official government records without a writing system. A quipu was a string of colored, knotted strings that could record population, number of troops, crop yields, size of animal herds, etc.
The colors of the strings stood for whatever was being counted for example, red string for number of warriors and yellow string for corn. Each quipu was different and was only meaningful to the person who was trained to make and interpret it. [more]