From 1000 BCE, most of Central America used similar types of calendars based on material objects and celestial constellations. The two most common calendars were the 260-day festival calendar and the 365-day solar calendar. The correlation between the two occurs every 52 years when both begin their new years. This is called the “Calendar Round” and the number became important in Central American cultures.
The 260-day calendar, called a tzolkin, consists of two wheels, a larger one of twenty days and a smaller one with the numbers one through thirteen. The number twenty was based on the digits of a “whole man” (i.e., fingers and toes) and the thirteen numbers represented their philosophy of thirteen directions in space. The early Central Americans believed that this ritualistic calendarrepresented an archetypal state of human and cosmic harmony.
Each rotation through the thirteen numbers represents one “week” in this system. The first, sixth, eleventh, and sixteenth weeks were special and very important; they created the four divisions of their year. Each of the twenty days was associated with tangible objects or animals and a deity. This created a sort of permanent fortune-telling machine and guided their destinies.
A list of the objects and deities associated with each day is available.
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