Saturday 21 June 2008

Stonehenge

Introduction

Stonehenge is a prehistoric monument on Salisbury Plain, north of Salisbury, in southwestern England, that dates from the late Stone and early Bronze ages (about 3000-1000 bc). The monument, now in ruins, consists of a circular group of large upright stones surrounded by a circular earthwork. Stonehenge is the best preserved and most celebrated of the megalithic monuments of Europe. It is not known for certain what purpose Stonehenge served, but many scholars believe the monument was used as a ceremonial or religious center.

Stonehenge is not a single structure, but a series of structures that were rebuilt, revised, and remodeled over a period of approximately 1,500 years. Little is known of Stonehenge’s architects. In the 17th century English antiquary John Aubrey proposed that Stonehenge was a temple built by Druids, a caste of Celtic priests encountered by the Romans as they conquered ancient Britain in the 1st century AD. Another early notion was that the Romans themselves constructed the monument. These theories were disproved in the 20th century, when archaeologists showed that work on Stonehenge began some 2,000 years before Celts, and later Romans, had arrived in the area. Today it is widely believed that Neolithic peoples of the British Isles began constructing the monument about 5,000 years ago.

Construction of Stonehenge
Excavations at Stonehenge since the 1950s suggest the monument was constructed in three main phases. The earliest phase of Stonehenge was completed by about 2900 bc. It consisted of a circular ditch 110 m (360 ft) in diameter and 1.5 m (5 ft) deep. Archaeologists believe deer antlers were used as picks to loosen the chalk bedrock. Excavated material was used to build a circular embankment along the inside rim of the ditch. Along the interior edge of the embankment the ancient architects dug 56 pits. These pits are named Aubrey Holes, after John Aubrey, who first observed them. The pits may once have held wooden posts.

In a second phase of construction, lasting from about 2900 to 2500 bc, several new timber structures arose at Stonehenge. Timber posts were erected in the flat ground at the center of the encircling ditch. Posts were also raised at a break in the ditch to the northeast, a place that served as an entrance to the site.
Stonehenge was radically and repeatedly transformed during a third phase of building, which lasted from about 2550 to 1600 bc. About 80 pillars of various types of igneous rock, called bluestones for their color, were erected near the center of the site in two concentric circles. The bluestones came from outcroppings in the Preseli Mountains of southwestern Wales, located roughly 220 km (137 mi) from Stonehenge. Transportation of the rock pillars, which weigh as much as 4 metric tons each, was a remarkable achievement and may have involved sea, river, and overland routes.

During this third phase of building, Stonehenge underwent a complicated sequence of remodeling. The double circle of bluestones was soon dismantled. Great blocks of a different kind of stone, a sandstone called sarsen, were brought from Marlborough Downs, located 40 km (25 mi) north of Stonehenge. Thirty of these new and much larger pillars of sarsen were erected in a circle with a diameter of about 33 m (108 ft). This structure is now known as the Sarsen Circle. Each pillar stood approximately 4 m (13 ft) above the ground. Mounted atop the 30 pillars was a continuous ring of sarsen crosspieces, called lintels. The lintels were matched together with tongue and groove joints and were attached to the pillars with mortise and tenon joints. With its engineering, design, and precise stonework, the Sarsen Circle is considered one of the most impressive features of Stonehenge. Of the 30 original sarsen pillars, 17 remain standing today along with six of the lintels.

Within the Sarsen Circle, a massive horseshoe-shaped structure was erected. The horseshoe, which opens to the northeast, toward the entrance to the structure, was constructed of five pairs of gigantic upright blocks of sarsen. Each block weighs 40 metric tons or more. A stone lintel on top of each pair makes each into a great archway called a trilithon (a word derived from Greek that means “three stones”). The trilithons increase in height toward the central and largest one, which measures 7 m (24 ft) above the ground. Three of the five original trilithons, complete with their lintels, remain standing today.

Several other features at the site are also associated with the third phase of construction. These include the Altar Stone, a block of greenish sandstone that sits at the base of the central trilithon near the center of the horseshoe. Once standing, the Altar Stone now lies flat against the earth, and—like the bluestones—came from southwestern Wales. Just inside the interior of the circular embankment, four stones, called station stones, were erected. Two of the stones are still standing. The station stones were situated approximately in line with the older Aubrey Holes. Imaginary lines connecting the stones opposite each other intersected at the very center of the monument. In addition, more sarsen stones were placed near the entrance to the monument. The two that survive are called the Slaughter Stone and the Heel Stone. The Heel Stone rises just outside the encircling ditch on the Avenue, a long earthwork structure that is marked by parallel banks. The Avenue is interpreted as a ceremonial approach to Stonehenge.

In later years, the bluestones were further rearranged. Eventually, some of the bluestones were used to erect a circle of pillars between the Sarsen Circle and the trilithon horseshoe, and a horseshoe of bluestone pillars was erected inside the trilithon horseshoe.

There are more than 1,000 stone circles in the British Isles, but Stonehenge is unique among them. No other circle has massive stones trimmed into neat shapes, like giant building bricks, or lintels perched atop them. The sophisticated engineering and joinery employed at Stonehenge suggest that it was built by people who were skilled in making great structures out of timber. Archaeologists now know that Stonehenge was just one of many prehistoric structures, collectively called henges, built of earth, river gravel, timber, or stone. Like the surviving stone circles, most were circular in shape.

Purpose of Stonehenge

Why Stonehenge was constructed remains unknown. Most scholars agree that it must have been a sacred and special place of religious rituals or ceremonies. Many have speculated that Stonehenge was built by Sun worshipers. The axis of Stonehenge, which divides the sarsen horseshoe and aligns with the monument’s entrance, is oriented broadly toward the direction of the midsummer sunrise. In nearby Ireland the celebrated megalithic monument Newgrange, built approximately at the same time as Stonehenge, was oriented toward the midwinter sunrise.

In the early 1960s American astronomer Gerald S. Hawkins theorized that Stonehenge was an astronomical observatory and calendar of surprising complexity. Hawkins suggested that ancient peoples used the monument to anticipate a wide range of astronomical phenomena, including the summer and winter solstices and eclipses of both the Sun and the Moon. The astronomical interpretation of Stonehenge remains popular today, despite many uncertainties. Some scholars are doubtful that the peoples who constructed Stonehenge and other sites of the era possessed the mathematical sophistication necessary to predict many of the events that Hawkins theorized. They note that Stonehenge’s architects may have been aware of the subtle movements of the Sun, Moon, and other heavenly bodies without having an analytically advanced understanding of astronomy.

The true purpose of Stonehenge is an enduring mystery. Modern observers can only speculate about what it meant to its builders and what compelling impulse drove them to invest so much labor and care in creating it.

A Recent Excavations

In 2006 excavations at Durrington Walls, about 3 km (less than 2 mi) from Stonehenge, uncovered a large settlement dating to 2600 or 2500 bc. The settlement consisted of wooden structures laid out in the same pattern as Stonehenge and, according to the archaeologists who conducted the excavations, probably housed the workers who built Stonehenge. However, the remains of large amounts of pottery and animal bones found at the site suggest that it was a place of feasting, which may mean that it housed people who came to Stonehenge to celebrate. In a separate area at Durrington Walls, archaeologists discovered the remains of houses surrounded by fences. They believe that these houses may have been used by priests or that they may have been used in cult rituals. In any case, the excavators believe that Durrington Walls and Stonehenge were closely connected and that Stonehenge was part of a much larger complex used for funeral rituals.


Reviewed By:

Christopher Chippindale, Ph.D.Curator, Cambridge University Museum of Archaeology & Anthropology in Cambridge, England. Author of Stonehenge Complete and The Archaeology of Rock-Art.

Further Reading
How to cite this article:"Stonehenge," Microsoft® Encarta® Online Encyclopedia 2008http://encarta.msn.com © 1997-2008 Microsoft Corporation. All Rights Reserved.

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