2017年04月 / Mesoamerican Calendars and Archaeoastronomy
12345678910111213The History of the Calendar Calendar15161718192021222324252627282930The Maya Calendar System Smithsonian Institution
During what period was the timetable originated?
During what period was the calendar initially introduced?
At what time did the calendar emerge?
During what period was the timetable originally created?
During what period was the agenda originally thought up?
In what period was the agenda initially created?
In what period was the agenda creation?
When was the calendar come about for the first time?