Calendar (Aztec)

The Aztec Calendar is a sophisticated system combining two main cycles: a 260-day religious calendar called the Tonalpohualli, and a 365-day agricultural calendar called the Xiuhpohualli. The Tonalpohualli features 20 day signs and 13 numbers, creating a cycle used for divination and ceremonial purposes. The Xiuhpohualli tracks the solar year with 18 months of 20 days plus five additional days considered unlucky. Both calendars interlock in a 52-year cycle, marking significant periods in Aztec society. The calendar reflects their deep understanding of astronomy, cosmology, and timekeeping, serving both practical and spiritual functions.