The Inca Empire in South America, one of the most powerful pre-Columbian societies, was known for many innovations — such as the architecture of Machu Picchu, an extensive road network, and a system ...

Receive emails about upcoming NOVA programs and related content, as well as featured reporting about current events through a science lens. Terence D'Altroy: It was about 2,400 miles from north to ...

Inca bureaucrats recorded all the goings-on in their bustling empire using knotted cords called khipu, where the position and order of the knots represented numbers. They relied on the khipu system to ...

The growth of the Inca Empire can only be described as meteoric. Though precise dates for its beginnings remain elusive, the realm known to the Inca as Tahuantinsuyu, or "The Four Parts Together," ...