The Aztec calendar is one of the Mesoamerican calendars, sharing the basic structure of calendars from throughout ancient Mesoamerica. The calendar consisted of a 365 day calendar cycle called xiuhpohualli (year count) and a 260 day ritual cycle called tonalpohualli (day count). These two cycles together formed a 52 year "century". Author unknown. 1 AI : 1,4 MB