Ancient Inca technology

"The Inca Empire was a complex, highly developed society that ruled ancient Peru for centuries. The civilization grew strong thanks to important advances in technology. This information-rich title covers the Incas roads and communications systems, buildings, bridges, terrace farming, and tools. Readers will also learn about important scientific innovations such as calendars, Quipu, the Incas understanding of astronomy, and their medicinal practices"--Amazon.com.