(CN) — Historians and archeologists have long suspected that Stonehenge was built to help ancient people keep time. Now they think they have a better idea on how exactly it worked.
Since it was first erected in what is now Wiltshire, England, some 4,000 to 5,000 years ago, the many mysteries of Stonehenge have kept experts scratching their heads on their quest for answers. Perhaps the most perplexing question behind the stone monument is also its most simple: why was it built in the first place?
While numerous theories have swirled throughout the centuries, such as the site being used as a burial ground or a place of pilgrimage for ancient Celts — not to mention tales from ancient British folklore that speak of Stonehenge being built by characters from the legends of King Arthur — the prevailing theory is it was built as a solar calendar. This is mainly because the entire structure appears to be intentionally situated towards the sunrise and is aligned with the winter and summer solstices.
Now, in a paper published Tuesday in the journal Antiquity, Timothy Darvill, a professor of archaeology at Bournemouth University and a leading Stonehenge authority, has announced he’s taken a new look into the solar calendar setup of Stonehenge. He believes he's worked out how the ancient timekeeper functioned.
“The proposed calendar works in a very straightforward way,” Darvill said. “Each of the 30 stones in the sarsen circle represents a day within a month, itself divided into three weeks each of 10 days.”
The calendar, according to this new research, also accounted for a leap day. The positioning of the stones suggest the calendar added an extra month onto each year and kept a series of stones outside the main circle that were used to help keep track of when an extra day was needed every four years.
This setup for tracking time, complete with a -day standard week, may seem a little strange compared to our modern calendars, but Darvill says timekeeping practices like this were actually fairly common thousands of years ago.
“Such a solar calendar was developed in the eastern Mediterranean in the centuries after 3000 B.C. and was adopted in Egypt as the civil calendar around 2700 and was widely used at the start of the Old Kingdom about 2600 B.C.,” he said, noting that influence from these ancient cultures could have informed the construction of Stonehenge.
The calendar was apparently so well thought out it even came equipped with natural calibration. Because the Stonehenge setup accounted for the leap day, both the winter and summer solstices would be framed by the exact same rock each year. This meant that if a year went by where some of the days were counted incorrectly, the ancient people would always find out when a solstice had occurred because the sun wouldn’t be in the right spot — at least according to their calculations.
Of course there are still countless more questions about this famed ruin left to be explored. We still are not entirely sure how those who built Stonehenge transported the 25-ton rocks to their current home and the construction techniques used by the builders are still shrouded in uncertainty.
But Darvill is optimistic the future will shed even more light on the mysteries behind arguably Earth’s most famous rock display. But whatever tomorrow holds, evidence of a solar calendar acting as the heart and soul of Stonehenge should fundamentally change how we look at not just the rocks themselves, but at the people who built them.
“Finding a solar calendar represented in the architecture of Stonehenge opens up a whole new way of seeing the monument as a place for the living,” he said. “A place where the timing of ceremonies and festivals was connected to the very fabric of the universe and celestial movements in the heavens.”
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