Explanation of the Mayan Calendar

Before the arrival of the Spaniards the Mayans used a highly sophisticated and accurate calendar which was called the Long Count. Where the Christian calendar dates from the birth of Christ, the Mayans used the birth or first rising of the planet Venus in the year 3114 BC. Thus, the movements of Venus formed the basis of their complex calendar that stretched over thousands of years.

The Mayans measured time not in years, but in clumps of days which were given ‘Long Count’ names
According to the Mayans the World began 1,867, 065 days ago, which is the equivalent to 3131 B.C. They measure time by:-

A Great Cycle was reckoned to last for 13 Baktuns-that is 1,872,000 days. The Mayans propecy is that the end of this present age will come during December, 2012.During our stay in Chichen-Itza, we had a calendar worked out to celebrate our 40th wedding anniversary in 1999.

If June 20th, 1999 is 1,867, 065 days since the world began this is equal to:-

Also the Sacred Calendar has 20 days-each represented pictorially by a glyph (skull)- in our case by chicchan (name of the day).

Also, Civil Calendar (i.e. our 365 day year) the month is ZoTZ also depicted by another skull.
Finally the Moon's age on June 20th, 1999 will be 1st quarter or 7.3 days (since lunar period is 28 days)

Each number is represented by a God
Each glyph is represented by a Skull
Date- Long Count
Sacred Calendar- 9 Chicchan represents the day

Civil Calendar- 13 ZOTZ (June)
i.e. Civil month

Moon's age -
1 quarter 7.3 days

In 1905 an American entrepeneur and writer published a paper called Maya Dates, which for the first time made it possible to correlate Maya Long Count dates with our present day calendar.
For further reading:- The Mayan Prophecies by Adrian G. Gilbert and Maurice Cotterell.