We begin with one of the oldest—and best-known—sacred places on the planet, the great megalithic stone circle known as Stonehenge, the ruins of which still loom majestically above Salisbury Plain in southwestern England. Like Rome, Stonehenge was not built in a day, but rather over a span of about fifteen hundred years, from about 2900 to 1500 B.C.E. The earliest phase in its construction involved the excavation of a circular ditch some 360 feet (110 meters) in diameter and five feet (1.5 meters) deep. Inside the ditch was an embankment, composed of excavated material, and just inside the embankment was a circle of fifty-six holes, or pits, that have come to be known as "Aubrey Holes" after their seventeenth-century discoverer, John Aubrey. These holes may have held posts of some sort.
The second phase in Stonehenge's construction, which lasted from 2900 to about 2500 B.C.E., saw the erection of wooden structures and posts in the center of the site. It was during the third and final phase (2500–1600 B.C.E.), however, that the monument we know today was created. Two concentric circles of approximately eighty huge stone pillars, quarried in southwestern Wales and known as "bluestones," from their bluish color, were erected in the center of the circle—only to be replaced several centuries later by a row of even bigger "sarsen" stones that were brought from Marlborough Downs, some twenty-five miles (forty kilometers) to the north. The thirty sarsen stones, each of which stands approximately thirteen feet (four meters) high, form a circle about 108 feet (33 meters) in diameter. Originally, they were topped by a circle of lintels; however, today only a few remain intact, together with seventeen of the original sarsen pillars.
Inside the so-called Sarsen Circle the builders erected a horseshoe-shaped structure composed of five pairs of huge sarsen blocks, weighing approximately forty metric tons each, each topped by an equally massive lintel forming a series of trilithons, or three-stone gateways, the largest of which rises twenty-four feet (seven meters). Within the horseshoe, next to the central trilithon, lies the formerly erect Altar Stone. In addition, four "station stones" are located just inside the embankment, and several more sarsen blocks were originally placed near the entrance to the site. The two that survive are the Slaughter Stone and the Heel Stone, which were placed just outside the ditch. The latter stone appears to have played a crucial part in the rituals that took place (and still take place) during the summer solstice.
In any case, it is the ruins of this final phase in Stonehenge's evolution that impress visitors today. Although there are over one thousand stone circles in Britain, the massive remains on Salisbury Plain are by far the most impressive, despite the collapse of most of the lintels and over half of the original stones. That it was an intensely sacred place dating back into the mists of prehistory is undoubted, despite the fact that the closely related questions of who built Stonehenge and what went on there have long been hotly debated.
The earliest theory, advocated by the aforementioned James Aubrey, was that it was built by the ancient Celtic Druids. However, while these mysterious white-clad priests probably venerated Stonehenge and performed rituals there, it long predated their appearance in Britain around 600 B.C.E. Other theories range from wandering Mycenaeans (on one of the sarsen stones there are markings that some scholars have identified as a Mycenaean double-ax) to Egyptians and even ancient astronauts. However the most likely candidates were the Bronze Age (3000–1000 B.C.E.) inhabitants of southern Britain, including the "Wessex people," whose precise linguistic affiliations are as yet unknown, although we do know that they shared a great many traits in common with the pre-Celtic populations of western Europe, including stone circles (compare Carnac in Brittany).
However, the questions of what it was used for can now be tentatively addressed, if not definitively answered. In the mid-1960s American astronomer Gerald S. Hawkins suggested that Stonehenge was an ancient astronomical observatory that was used to calculate a variety of celestial events, including both lunar and solar eclipses, as well as the summer and winter solstices. To this day, the sun rises over the Heel Stone on 21 June, the summer solstice, and thousands of pilgrims, including latter-day "Druids," flock to Stonehenge every year on that date to watch this occur. If Hawkins is correct, the calendar, as well as the solar and lunar cycles, must have loomed large indeed in the beliefs systems of those who built the monument. However, this hypothesis is by no means universally accepted. Other scholars assert that, while it was clearly a place where extremely important rituals took place, some of them perhaps involving animal and perhaps human sacrifices (hence the "Slaughter Stone"), it was not a primordial "computer" designed to facilitate the calculation of astronomical events. In short, a definitive interpretation of the fundamental meaning and purpose of this remarkable place remains elusive.
Nevertheless, anyone making the trek to Salisbury Plain for the first time cannot help but be awestruck at the sight of those mighty stones silhouetted against the sky. The enduring sacredness of Stonehenge is underscored by the fact that, unlike the other megalithic monuments of Britain, such as the great stone circle at Avebury, some thirty miles (forty-eight kilometers) to the north, it has never been intruded upon by a town or village.
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