The calendars produced by both the Mayan and ancient Mesopotamian civilizations were accurate for their time and served various purposes in their respective cultures.
Mayan Calendar
The Mayans developed several interconnected calendars including the Tzolk'in and the Haab
The Tzolk'in was a 260-day ceremonial calendar, and the Haab' was a 365-day solar ca lendar.
The Mayan calendar system was quite sophisticated, incorporating a Long Count for tracking longer time periods.
Mesopotamian Calendar
The ancient Mesopotamians including the Sumerians and Babylonians, used various calendars, with some based on the lunar cycle.
The Babylonians, for example, employed a lunisolar calendar that combined lunar and solar elements.
Accuracy and Use Today
While these ancient calendars were accurate for their time, they were eventually replaced by more precise modern calendars.
Today, we don't use these ancient calendars for practical timekeeping, but they are studied for historical and cultural insights.