Note on the ancient Mexican calendar system
Reconstruction, by Zelia Nuttall
The Aztecs used a 260-day divinatory calendar that they called the tonalpoualli. They named each year for the tonalpoualli date on which it began. The Aztec day names and the Aztec date notations were simpler than those of the Maya.
More Exhibit Items
The Aztec Year & the Aztec Month