You must absolutely go to the this website to see the collection of stunning pictures. I don't want to replicate them all here. The text below is taken from the website, but is more tied into the pictures there.
Egyptian & Mayan-Aztec Calendars: Incredibly Sophisticated Earliest Works of Art
We are continuing our historical art overview (see for example, our "Mysterious Non-Egyptian Pyramids"), this time going all the way back to the beginning of the recorded history. Around 5,000 BC first calendars made their appearance, and set the standard by which we measure our months and days today.
Regardless of what you think about Mayan Calendar concerning 2012, you have to admit their representation of time flow was simply stunning:
Time Out of Time
One of our readers writes "I have a little replica, it's fantastic. Every year has a "no time" period - days "outside the calendar", to freely celebrate life." Well, actually, there are in total five "Nameless Days" (more info) at the end of every Mayan solar year - so called Wayeb' "Time Out of Time", a period for transition and preparation for the next year. Beside the obvious "free time" aspect, these days were considered sacred and quite mysterious "Days of Awe":
"During Wayeb, portals between the mortal realm and the Underworld dissolved. No boundaries prevented the ill-intending deities from causing disasters." For those interested, in 2012 the Wayeb period falls on March 28 - April 1 (source).
Ancient Egyptian Astronomical Calendar: Into the Wide Blue Yonder
The calendar system itself is one of the oldest, dated around 5,000 BC. This is also a truly spectacular presentation, full of pictoglyphs on paper made from the papyrus plant:
2012. "Stunning Art of Ancient Calendars ". Dark Roasted Blend. Posted: February 26, 2012. Available online: http://www.darkroastedblend.com/2012/02/stunning-art-of-ancient-calendars.html