Fragmented into six pieces, divided between Mexico and the US, the stone is known as The Tortuguero Monument 6
Relax doomsayers, the Maya people did not really mark their calendar for the end of the world on December 21, 2012.
As tourists book hotels rooms in Mexico's Maya Riviera and Guatemalan resorts ahead of next month's fateful date, experts are busy debunking the doomsday myth.
The apocalyptic prophecy that has inspired authors and filmmakers never appears in the tall T-shaped stone calendar that was carved by the Maya around the year 669 in southeastern Mexico.
In reality, the stone recounts the life and battles of a ruler from that era, experts say. Plus, the last date on the calendar is actually December 23, 2012, not the 21st, and it merely marks the end of a cycle.
So no need to build giant arks, because the terrible floods, earthquakes and volcanic eruptions depicted in the Hollywood blockbuster "2012" were not prophesied by the Mayas.
"The Mayas had a cyclical idea of time. They were not preoccupied with the end of the world," Mexican archeologist Jose Romero told AFP.
The stone, known as Monument 6, was located in El Tortuguero, an archeological site that was discovered in 1915.
Broken in six pieces, the different fragments are exhibited in US and Mexican museums, including Tabasco's Carlos Pellicer Camara Anthropology Museum and New York's Metropolitan Museum.
The first study on the stone was published by a German researcher in 1978. Since then, various archeologists have examined its significance and agree that it refers to the December 23 date.
"The last inscription refers to December 23, 2012, but the central theme of Monument 6 is not the date, it's not the prophecies or the end of the world. It's the story of (then ruler) Bahlam Ajaw," Romero said.
The final date represents the end of a cycle in the Mayan long count calendar that began in the year 3114 before Christ. It is the completion of 13 baak t'uunes, a unit of time equivalent to 144,000 days.
"It is not the end of the Mayan long count calendar, which is endless. It's the beginning of a new cycle, that's all," said Mexican historian Erick Velasquez.
Though the Maya made prophecies, they looked at events in the near future and were related to day-to-day concerns like rain, droughts, or harvests.
The belief that the calendar foresees the end of the world comes from Judeo-Christian interpretations, the experts said.
Velasquez warned against giving too much weight to Monument 6, noting that it is just one of more than 5,000 stones from the Mayan culture that have been studied.
The Earth still has a few years left, even in eyes of the ancient Maya: Some stones refer to the year 7000.