Mesoamerican calendars was of ritual significance to a number of Mesoamerican cultures. A third major calendar form known as the Long Count is found in the inscriptions of several Mesoamerican cultures, most famously those of the Maya civilization who developed it to its fullest extent during the Classic period (ca. 200–900 CE). The Long Count provided the ability to uniquely identify days over a much longer period of time, by combining a sequence of day-counts or cycles of increasing length, calculated or set from a particular date in the mythical past. Most commonly, five such higher-order cycles in a modified vigesimal (base-20)
Mesoamerican calendars (year count) and "tonalpohualli" (day count) respectively. The Veintena was called "metztli" (moon), and the five unlucky days at the end of the solar year were called "nemontemi". Other calendar cycles were also recorded, such as a lunar calendar, as well as the cycles of other astronomical objects, most importantly Venus. Mesoamerican calendars Mesoamerican calendars are the calendrical systems devised and used by the pre-Columbian cultures of Mesoamerica. Besides keeping time, Mesoamerican calendars were also used in religious observances and social rituals, such as for divination. The existence of Mesoamerican calendars is known as early as ca. 500 BCE, with