The Sacred Round

by John P. Pratt (updated 9 May 2011)

The 260-day Sacred Round (also called the tzolkin) is the heart of the Aztec Calendar, the Mayan calendar and nearly every native calendar of the Americas. The sacred round is composed of two cycles, one of 20 named days, and one of 13 numbered days, each of which continuously repeats. It takes 260 days for the two cycles to realign on the beginning day of each cycle (260 = 20 x13), so the Sacred Round has 260 days.

The details are described below, but it should be noted at the outset that to this author, the Sacred Round is important enough that it could be used by even modern people, rather than being only be a curious artifact of an ancient culture. To facilitate its use today, I include a table of all 260 days which can be used as a perpetual calendar, using both written names and also modern icons, created just for this usage.

The 20-day Vientena

**The 20 day glyphs from the Aztec Calendar stone.**

1. Light


2. Wind

3. Temple

4. Dragon

5. Serpent

6. Skull

7. Deer

8. Rabbit

9. Water

10. Dog

11. Monkey

12. Grass

13. Reed

14. Jaguar

15. Eagle

16. Condor

17. Quake

18. Flint

19. Storm

20. Flower

The fundamental cycle is the 20-day count, called the vientena. That is Spanish for a "group of twenty" even as docena, reminiscent of "dozen", is Spanish for a group of twelve. Similarly, trecena is a group of thirteen.

Each of the days is named and has an associated picture or glyph. The 20 day glyphs are shown in a circle in the famous Aztec Calendar Stone. This illustration is only of the central part of that calendar. The 20-day cycle begins at the top and goes around counter-clockwise.

The names were chosen by this author as the best English words to describe the idea. Most tribes had slight variations of the pictures and of what the name should be. For example, the first figure was either a crocodile, a water lily, or the sun. In every case, according to the Mayan priests, the original idea was that of the conception of new life. The crocodile and water lily, both floating in the water, fit the image of a fetus in the womb. The Olmec figure of the sun may represent the moment when the spark of life begins. I chose the word "Light" to best summarize this idea, and have proposed the figure of a sunrise to symbolize the first flash of dawn as representing that spark. A comparison of the Mixtec glyphs (from the Codex Nuttall) and my proposed modern icons are shown at left. The Mixtec figures are only slightly different from the Aztec.

The days were said by the Mayans to represent the steps in a person's life (from before birth to after resurrection). Thus, after the first day (Light) which represents conception, the second (Wind) is quickening, when the spirit enters the baby still in the womb, and the third (Temple) is the day of birth. The fourth (Dragon) is the day when evil is first allowed into the child's life, and the fifth (Serpent) seems to represent the entire experience of mortality. The sixth (Skull) represents death, and the seventh (Deer) represents the fleeting journey into the spirit world. The final thirteen steps are less clear, as is our understanding of life after death. The names and symbolism are explained in more detail on a separate page.

Note that the circular arrangement is important because there are several pairs of opposites. For example, the fifth day in the cycle is "Serpent," and directly opposite the serpent is the "Eagle." The eagle/serpent pair was so important to the Aztecs that their capital (now Mexico City) was founded where they saw the eagle with the serpent in its talons (now immortalized on the Mexican flag.)

The vientena is also the fundamental cycle of the Mayan Long Count, which is not discussed here. Moreover, Native American astrology, which assigns similar traits to people, is based on the day of the vientena on which they are born. This is described in a book entitled The Cherokee Sacred Calendar, by Raven Hail.

The 13-day Trecena

**The Sacred Round is like two connected gears. The date indicated is 1 Light, the first day of the Sacred Round. The next day will be 2 Wind.**

The 13-day cycle, called the trecena, simply numbers the days rather than using pictures. That is, the days are numbered from 1 to 13 and then that cycle repeats indefinitely. The two cycles continue separately from each other. It is very similar to how there are seven days in a week, and they just keep repeating. No extra days are ever inserting into the week, and none are ever inserted into either the trecena or the vientena.

The two cycles each separately move through one day at a time, so the effect is similar to two gears, one with 13 cogs and the other with 20, as shown in the illustration. Thus, the Sacred Round begins at the position shown on the day 1 Light. The next day is 2 Wind and then 3 Temple. That may sound confusing if were expecting 1 Light to be followed by 2 Light and then 3 Light. But we do the same thing on our modern Gregorian calendar. The day after Monday the 1st (of a month) is Tuesday the 2nd. That is because the week of seven days progresses daily even as do the days of the month. The thirteenth day of the cycle is 13 Reed. The following day is 1 Jaguar, because the trecena starts over, but the vientena continues on through all 20 figures. It takes 260 days to get back to the starting position (13 x 20 = 260), so the Sacred Round contains 260 days.

One can ask whether the Sacred Round consists of 13 cycles of 20 days or 20 cycles of 13 days. Most Native Americans think of the Sacred Round as 20 trecenas. Each is named for its first day. Thus the first trecena is named 1 Light, for its first day. The second is 1 Jaguar. The entire Sacred Round is listed on a separate page using both written names and modern icons. A Native American example of the thirteenth trecena "1 Quake" is illustrated in a wikipedia article).

Almost every author I have read gets this backwards. The only reason modern authors usually list the Sacred Round as 13 groups of 20 is that it is much easier to make a table of 260 numbers rather than 260 words or glyphs. But it is important to get it right if one actually wants to use it.