Of all the ancient calendar systems, the Maya and other Mesoamerican systems are the most complex and intricate. They used 20-day months, and had two calendar years: the 260-day Sacred Round, or tzolkin, and the 365-day Vague Year, or haab.
A different calendar was used to track longer periods of time and for the inscription of calendar dates (i.e., identifying when one event occurred in relation to others). This is the Long Count.
Most historians think that 4 Ahau 8 Cumku (most likely August 11, 3114 bce) was the base date used by the Maya for the start of the “Long Count” and the first “Great Cycle,” a period of 5,125 years that ends on December 21, 2012 ce.
In the Maya Long Count, the previous world ended after 13 bʼakʼtuns, or roughly 5,125 years. The Long Count’s “zero date” was set at a point in the past marking the end of the third world and the beginning of the current one, which corresponds to 11 August 3114 BC in the proleptic Gregorian calendar.
The current practice of referring to the current baktun as ” baktun 13” or “thirteenth baktun ” may stand, even though it is properly the fourteenth baktun .
Scholars have suggested a number of potential reasons for the downfall of Maya civilization in the southern lowlands, including overpopulation, environmental degradation, warfare, shifting trade routes and extended drought. It’s likely that a complex combination of factors was behind the collapse.
Mysterious Decline of the Maya From the late eighth through the end of the ninth century, something unknown happened to shake the Maya civilization to its foundations. One by one, the Classic cities in the southern lowlands were abandoned, and by A.D. 900, Maya civilization in that region had collapsed.
Allen Christenson, professor of comparative arts and letters and an expert on Mayan society, explained that although the Maya couldn’t predict the exact day of an eclipse , they could predict eclipse seasons by noting when Venus rose above the horizon just before sunrise.
The Maya recorded time in a series of cycles, including 400-year chunks called baktuns. It’s these baktuns that have led to rumors of an end-of-the-world catastrophe on Dec . 21 , 2012 — on that date, a cycle of 13 baktuns will be complete.
The Mayan calendar is an ancient system of three interlacing calendars : the Long Count, the Tzolkin and the Haab. The Long Count is an astronomical calendar . Each cycle is 2,880,000 days long. The Tzolkin is a 260-day calendar used for religious events, and the Haab is a 365-day solar calendar .
At the end of the 13th baktun, the Long Count calendar resets to 0.0. 0.0. 0. The ancient Maya reportedly believed that with each end of the Universal cycle, the Universe itself would “reset” by ending and starting over — not just the calendar — hence the doomsday interpretation.
The Maya Calendar contains two separately working calendars which function simultaneously: the Haab, or civil calendar of 365 days in an 18 month period of 20 days each, and the Tzolkin, or sacred calendar , of 260 days divided into three groups of months of 20 days.