For a long time, many believed that Stonehenge, one of the most iconic monuments in the world, was an ancient calendar due to its alignment with the summer and winter solstices. However, the precise way it functioned remained a mystery. Recently, a team of researchers proposed that Stonehenge could have operated like a solar calendar, similar to the ancient Egyptian calendar, which was based on a year composed of 365.25 days.
Each stone in the large, mysterious sarsen circle at Stonehenge represented a day within a month. These large boulders, known as sarsens, formed a perpetual calendar where people could track the winter solstice sunset annually. This system allowed those living near Stonehenge, now located in Wiltshire, UK, to keep track of the days and months of the year. This revelation came after a significant discovery in 2020, where researchers identified the source of 50 of the 52 sarsens that make up the iconic stone circle. They analyzed the chemical composition of these stones and traced their origins to the West Woods in Wiltshire, about 15 miles from Stonehenge.
Not only did these 50 sarsens come from the same source, but they were also placed in their current positions simultaneously, forming the outer circle of Stonehenge. Inside this circle, there is a horseshoe-shaped inner ring composed of smaller rocks known as bluestones, which were traced back to Wales. The sarsens share a common chemistry, consisting of over 99% silica with trace elements. Two sarsens, however, were different from the rest and arranged in three distinct formations at Stonehenge: thirty formed a large stone circle, four station stones were in a rectangular formation outside the circle, and the rest were constructed into five trilithons within the stone circle.
The thirty uprights in the main sarsen ring could represent the days of the month. When multiplied by twelve, this equals 360 days. Adding the five central trilithons results in 365 days, aligning with the solar calendar. The four station stones were likely used to keep track of the leap day added every four years.
Stonehenge’s construction began about five thousand years ago, taking over a thousand years to complete. The monument seen today is not the original; many of its old bluestones and sarsens have been broken or removed over time. Stonehenge was built in four stages: first, a circular enclosure with a diameter of about 330 feet (100 meters) and 56 pits; next, a horseshoe of sarsen trilithons was added; then, a nearly two-mile-long ceremonial avenue was constructed, likely tracing the path of the bluestones moved from the Aubrey holes to the Q and R holes. In the final stage, builders modified the stones and etched carvings into the sarsens.
Despite the lack of written records about the construction techniques, theories suggest that the builders used woodworking techniques to slot the stones together, employing mortise holes and protruding tenons. Timber poles were used as brace support, and the stones were hauled into position with ropes and secured with rubble.
Stonehenge’s stones have unique acoustic properties, producing a loud clanging sound when struck, which might have been a reason for their transportation over long distances. In some ancient cultures, these rocks were believed to have healing powers. Stonehenge attracts over a million visitors annually, although it is now roped off to prevent further erosion.
Originally, Stonehenge had two entrances: a wide one to the northeast and a smaller one to the south. Many more gaps are visible today, mainly due to later tracks that crossed the monument. The ground within Stonehenge has been severely disturbed over time by visitors and excavations, including those by Charles Darwin studying earthworms.
Various theories about Stonehenge’s purpose have been proposed, from predicting solar and lunar eclipses to serving as a monument to ancestors. The average sarsen weighs 25 tons, with the largest weighing around 30 tons. Visitors can see a replica sarsen stone behind the visitor center to understand their size. Stonehenge also features five Neolithic houses based on archaeological evidence, indicating that people celebrated and feasted in the area around 4500 BCE, when the sarsen stones were brought to Stonehenge.
During the construction of Stonehenge, people transitioned from the Stone Age to the early Bronze Age, becoming more mobile and engaging in trade and communication, even internationally. This increased interaction helped spread the word about Stonehenge and contributed to the monument’s enduring mystery and fascination.
