Stonehenge may have been a giant calendar and now we know how it works

By Alison George.

It was thought that the calendar system of the ancients was based on the alignment of the summer and winter solstices. A new analysis shows that it could have been similar to the solar calendar used in ancient Egypt, with each stone representing a day within a month.

The analysis was carried out by Tim Darvill of Bournemouth University, UK. The ancient people who lived near the monument would have been able to keep track of days and months.

The discovery in 2020 that most of the sarsen stones were quarried from the same location 25 kilometres away unlocked the calendar system.

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The message to me was that they have a unity to them, because all except two of the sarsen at Stonehenge come from that single source. They were intended for a common purpose. He looked for clues in the numbers.

The sarsen were arranged in three different formations at around 2500 BC, the large stone circle that dominates the monument, 4 station stones, and the rest were constructed into 5 trilith.

There are 30 uprights around the main sarsen ring at Stonehenge. The summer and winter are framed by the same pair of stones every year.

David Nash at the University ofBrighton, UK, says that the calendar system makes a lot of sense.

Mike Pearson of University College London, UK., says that it fails to convince and that the numbers don't really add up. There is a way to try to make the numbers fit.

Read more: Stonehenge was built with bits of an older Welsh Stone Age monument

A solar calendar with an extra month of five days was developed in the eastern Mediterranean and was used in ancient Egypt.

The five extra days in the Egyptian calendar were very significant, according to an expert in ancient calendars. The tallest stone at the monument, part of one of the trilithons, points to the sunrise in the middle of winter, and this has led Darvill to think that the five trilithon structures at Stonehenge might have marked a five-day mid-winter celebration.

The similarity between the calendar used in ancient Egypt and the one used in the UK suggests that the idea for the system may have come from far away. Recent archaeological finds support the idea of long-distance travel. A red glass bead found 2 km from the monument appears to have been made in Egypt, and an analysis of the Amesbury archer's body shows that he was born in the Alps and came to Britain as a teenager.

I wonder if you need to invoke the Egyptians. We can't imagine that the people who built Stonehenge created the whole system on their own. It won't take long to figure out how many days you need in the year, because they knew when the solstice was.

The journal has a reference to Antiquity.

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