The universe came into being on 13 August, 3114 BC. This is day zero according to the Mayan Long Count, and is the date all other days are reckoned from.
Not much is known about the Mayan civilization which flourished in the Yucatan Peninsula, Mexico, between about 300 BC to 900 AD. A limited part of our knowledge about them concerns their calendars. The Mayans used around 17 different calendars to divide up their time. They were based on the stars and planets, the Earth and Moon, and were very complicated. The Mayans are possibly the only civilization to count from zero. Our calendar starts with the first day of January, but they had zero days at the beginning of theirs.
The main calendars, which would have been used by the general population, were the Tun-Uc, the Haab, and the Tzol'kin, based on the cycles of the Earth, Moon and The Pleiades1 respectively. Here are some of the calendar systems that the Maya used:
The Long Count
The Long Count, as it is called by modern archaeologists, set the date from when the Mayans thought that time began, in 3114 BC. Using the Long Count it was possibly for the Maya to date any event, for example the construction of a monument, or to calculate an exact amount of time from when they thought the universe began. However, the Long Count wasn't just a string of days; they were grouped into other units too:
|Unit||Number of Smaller Units||Number of days|
|1 K'in||1 day|
|1 Winal2||20 K'in||20 days|
|1 Tun||18 Winal||360 days|
|1 K'atun||20 Tun||7,200 days|
|1 Bak'tun||20 K'atun||144,000 days|
|1 Great Cycle||13 Bak'tun||1,872,000 days|
The nearest unit to a year the Long Count has is the Tun, 360 days. Because this is five days out from the solar year of 365.25 days, the Long Count isn't practical for everyday usage.
The Haab was the civil calendar. It was split into 18 months of 20 days, like a Tun, but it had five 'phantom' days at the end of the year to make it correspond with the Earth's rotation around the Sun. The days of the months in the Haab were numbered from 0 - 19, rather than 1 - 20, as they might have been if it were a Western calendar. The Maya believed that a different god ruled over each month. The zero day of a new month occurred when one god passed his burden of time on to the next; rather than being instantaneous, as it is in our calendar, this process took a whole day. During the five 'phantom' days at the end of the year, the people wouldn't wash themselves or do any work, in case something went wrong.
This calendar was based on the 26,000 year cycle of the Pleiades, but lasted 260 days. The numbers 13 and 20 were both sacred to the Mayans. There were 13 gods of their 'upper world' and the number 20 represented man. The Tzol'kin was a very complicated counting system. There were 20 day names and 13 numbers which went together. So to start with, the numbers 1 - 13 went with the first 13 days. Then numbers 1 through to 7 were paired with days 14 through 20. After that day one came again, this time paired with the number eight.