Ritual solstice structure 1,000 years older than Stonehenge unearthed in Czech Republic

Archaeologists in the Czech Republic have discovered a prehistoric structure they believe was a ritual center linked to the movements of the sun and moon. The center is around 6,500 years old — about 1,000 years older than Stonehenge.

The structure was discovered at Chleby in the Central Bohemian Region. Archaeologists found a circular enclosure consisting of a ditch that was about 750 feet (230 meters) in diameter and 8 feet (2.5 m) deep. Twelve entrances that led to the center of the enclosure were located in different spots around the ditch, the team said in an Aug. 18 statement .

Archaeologists suspect that wooden posts likely created the walls of the enclosure. Based on animal bones found in the ditch, experts think that the entryways were decorated with bull skulls and horns.

"The cult of the bull was an important religious symbol among the first farming communities and is known from many parts of prehistoric Europe," Jan Turek , an archaeologist at Charles University in Prague who is involved in the research, said in the statement. Bulls in these Neolithic cultures were likely symbols of strength and fertility.

The shape and orientation of the mysterious structure are unusual for a Stone Age site, the archaeologists noted.

"Circular enclosures are completely unknown in our region for this period, which already makes the site exceptional," Petr Krištuf , an archaeology professor at the University of West Bohemia in the Czech Republic who is leading the research team, said in the statement. "But when we began to analyze the positioning of the entrances in detail, it became clear that their arrangement was not random. Their geometry creates a system that made it possible to observe the most significant moments of the solar and lunar cycles."

Specifically, the 12 entrances were oriented so that people inside the enclosure could observe important astronomical events, such as the moon's most extreme position on the horizon during its 18.6-year cycle . People could also observe sunrise on the summer solstice , the longest day of the year, and sunset on the winter solstice , the shortest day of the year, through the structure's entrances.

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