Stonehenge is a prehistoric monument located in the English county of Wiltshire, about 8 miles (13 km) north of Salisbury. One of the most famous prehistoric sites in the world, Stonehenge is composed of earthworks surrounding a circular setting of large standing stones. Archaeologists believe that the standing stones were erected around 2200 BC and the surrounding circular earth bank and ditch, which constitute the earliest phase of the monument, have been dated to about 3100 BC. The site and its surroundings were added to the UNESCO's list of World Heritage Sites in 1986 in a co-listing with Avebury henge monument, and it is also a legally protected Scheduled Ancient Monument. Stonehenge itself is owned by the Crown and managed by English Heritage while the surrounding land is owned by the National Trust.

Etymology

Christopher Chippindale's Stonehenge Complete gives the derivation of the name Stonehenge as coming from the Old English words "stan" meaning "stone", and either "hencg" meaning "hinge" (because the stone lintels hinge on the upright stones) or "hen(c)en" meaning "hang" or "gallows" or "instrument of torture". Medieval gallows consisted of two uprights with a lintel joining them, resembling Stonehenge's trilithons, rather than looking like the inverted L-shape more familiar today.

The "henge" portion has given its name to a class of monuments known as henges. Archaeologists define henges as earthworks consisting of a circular banked enclosure with an internal ditch. As often happens in archaeological terminology, this is a holdover from antiquarian usage, and Stonehenge cannot in fact be truly classified as a henge site as its bank is inside its ditch. Despite being contemporary with true Neolithic henges and stone circles, Stonehenge is in many ways atypical. For example, its extant trilithons make it unique. Stonehenge is only distantly related to the other stone circles in the British Isles, such as the Ring of Brodgar.

History

The Stonehenge complex was built in several construction phases spanning at least 3000 years, although there is evidence for activity both before and afterwards on the site, perhaps extending its time frame to 6500 years.

Dating and understanding the various phases of activity at Stonehenge is not a simple task; it is complicated by poorly kept early excavation records, surprisingly few accurate scientific dates and the disturbance of the natural chalk by periglacial effects and animal burrowing. The modern phasing most generally agreed by archaeologists is detailed below. Features mentioned in the text are numbered and shown on the plan, right, which illustrates the site as of 2004. The plan omits the trilithon lintels for clarity. Holes that no longer, or never, contained stones are shown as open circles and stones visible today are shown coloured.

Before the monument (8000 BC forward)

Some archaeologists have found four (or possibly five, although one may have been a natural tree throw) large Mesolithic postholes which date to around 8000 BC nearby, beneath the modern tourist car-park. These held pine posts around 0.75 m (2.4ft) in diameter which were erected and left to rot in situ. Three of the posts (and possibly four) were in an east-west alignment and may have had ritual significance; no parallels are known from Britain at the time but similar sites have been found in Scandinavia. At this time, Salisbury Plain was still wooded but four thousand years later, during the earlier Neolithic, a cursus monument was built 600 m north of the site as the first farmers began to clear the forest and exploit the area. Several other early Neolithic sites, a causewayed enclosure at Robin Hood's Ball and long barrow tombs were built in the surrounding landscape.

Stonehenge 1 (ca. 3100 BC)

The first monument consisted of a circular bank and ditch enclosure made of Late Cretaceous (Santonian Age) Seaford Chalk, (7 and 8) measuring around 110 m (360 feet) in diameter with a large entrance to the north east and a smaller one to the south (14). It stood in open grassland on a slightly sloping but not especially remarkable spot. The builders placed the bones of deer and oxen in the bottom of the ditch as well as some worked flint tools. The bones were considerably older than the antler picks used to dig the ditch and the people who buried them had looked after them for some time prior to burial. The ditch itself was continuous but had been dug in sections, like the ditches of the earlier causewayed enclosures in the area. The chalk dug from the ditch was piled up to form the bank. This first stage is dated to around 3100 BC after which the ditch began to silt up naturally and was not cleared out by the builders. Within the outer edge of the enclosed area was dug a circle of 56 pits, each around 1 m in diameter (13), known as the Aubrey holes after John Aubrey, the seventeenth century antiquarian who was thought to have first identified them. The pits may have contained standing timbers, creating a timber circle although there is no excavated evidence of them. A small outer bank beyond the ditch could also date to this period.

Stonehenge 2 (ca. 3000 BC)

Evidence of the second phase is no longer visible. It appears from the number of postholes dating to this period that some form of timber structure was built within the enclosure during the early 3rd millennium BC. Further standing timbers were placed at the northeast entrance and a parallel alignment of posts ran inwards from the southern entrance. The postholes are smaller than the Aubrey Holes, being only around 0.4 m in diameter and are much less regularly spaced. The bank was purposely reduced in height and the ditch continued to silt up. At least twenty-five of the Aubrey Holes are known to have contained later, intrusive, cremation burials dating to the two centuries after the monument's inception. It seems that whatever the holes' initial function, it changed to become a funerary one during Phase 2. Thirty further cremations were placed in the enclosure's ditch and at other points within the monument, mostly in the eastern half. Stonehenge is therefore interpreted as functioning as an enclosed cremation cemetery at this time, the earliest known cremation cemetery in the British Isles. Fragments of unburnt human bone have also been found in the ditch fill. Late Neolithic grooved ware pottery has been found in connection with the features from this phase providing dating evidence.

Stonehenge 3 I (ca. 2600 BC)

Archaeological excavation has indicated that around 2600 BC, timber was abandoned in favour of stone and two concentric crescents of holes (called the Q and R Holes) were dug in the centre of the site. Again, there is little firm dating evidence for this phase. The holes held up to 80 standing stones (shown blue on the plan) 43 of which, the bluestones (dolerite, a holocrystine igneous rock), were thought for much of the 20th century to have been transported by humans from the Preseli Hills, 250 km away in modern day Pembrokeshire in Wales. A current (2007) theory is that they were brought from glacial deposits much nearer the site, which had been carried down from the northern side of the Preselis to southern England by the Irish Sea Glacier. Other standing stones may well have been small sarsens, used later as lintels. The stones, which weighed about four tons, consisted mostly of spotted Ordovician dolerite but included examples of rhyolite, tuff and volcanic and calcareous ash. Each measures around 2 m in height, between 1 m and 1.5 m wide and around 0.8 m thick. What was to become known as the Altar Stone (1), a six-ton specimen of green micaceous Silurian-Devonian sandstone, twice the height of the bluestones, is derived from either South Pembrokeshire or the Brecon Beacons and may have stood as a single large monolith.

The north eastern entrance was also widened at this time with the result that it precisely matched the direction of the midsummer sunrise and midwinter sunset of the period. This phase of the monument was abandoned unfinished however, the small standing stones were apparently removed and the Q and R holes purposefully backfilled. Even so, the monument appears to have eclipsed the site at Avebury in importance towards the end of this phase and the Amesbury Archer, found in 2002 three miles (5 km) to the south, would have seen the site in this state.

The Heelstone (5), a Tertiary sandstone, may also have been erected outside the north eastern entrance during this period although it cannot be securely dated and may have been installed at any time in phase 3. At first, a second stone, now no longer visible, joined it. Two, or possibly three, large portal stones were set up just inside the north eastern entrance of which only one, the fallen Slaughter Stone (4), 16 ft (4.9 m) long, now remains. Other features loosely dated to phase 3 include the four Station Stones (6), two of which stood atop mounds (2 and 3). The mounds are known as 'barrows' although they do not contain burials. The Avenue, (10), a parallel pair of ditches and banks leading 3 km to the River Avon was also added. Two ditches similar to Heelstone Ditch circling the Heelstone, which was by then reduced to a single monolith, were later dug around the Station Stones.

Stonehenge 3 II (2450 BC to 2100 BC)

The next major phase of activity at the tail end of the 3rd millennium BC saw 30 enormous Oligocene-Miocene sarsen stones (shown grey on the plan) brought from a quarry around 24 miles (40 km) north of Stonehenge, on the Marlborough Downs. The stones were dressed and fashioned with mortise and tenon joints before 30 were erected as a 33 m (108 ft) diameter circle of standing stones with a 'lintel' of 30 stones resting on top. The lintels were joined to one another using another woodworking method, the tongue in groove joint. Each standing stone was around 4.1 m (13.5 feet) high, 2.1 m (7.5 feet) wide and weighed around 25 tons. Each had clearly been worked with the final effect in mind; the orthostats widen slightly towards the top in order that their perspective remains constant as they rise up from the ground while the lintel stones curve slightly to continue the circular appearance of the earlier monument. The sides of the stones that face inwards are smoother and more finely worked than the sides that face outwards. The average thickness of these stones is 1.1 m (3.75 feet) and the average distance between them is 1 m (3.5 feet). A total of 74 stones would have been needed to complete the circle and unless some of the sarsens were removed from the site, it would seem that the ring was left incomplete. Of the lintel stones, they are each around 3.2 m long (10.5 feet), 1 m (3.5 feet) wide and 0.8 m (2.75 feet) thick. The tops of the lintels are 4.9 m (16 feet) above the ground.

Within this circle stood five trilithons of dressed sarsen stone arranged in a horseshoe shape 13.7 m (45 feet) across with its open end facing north east. These huge stones, ten uprights and five lintels, weigh up to 50 tons each and were again linked using complex jointings. They are arranged symmetrically; the smallest pair of trilithons were around 6 m (20 feet) tall, the next pair a little higher and the largest, single trilithon in the south west corner would have been 7.3 m (24 feet) tall. Only one upright from the Great Trilithon still stands; 6.7 m (22 ft) is visible and a further 2.4 m (8 feet) is below ground.

The images of a 'dagger' and 14 'axe-heads' have been recorded carved on one of the sarsens, known as stone 53. Further axe-head carvings have been seen on the outer faces of stones known as numbers 3, 4, and 5. They are difficult to date but are morphologically similar to later Bronze Age weapons; recent laser scanning work on the carvings supports this interpretation. The pair of trilithons in north east are smallest, measuring around 6 m (20 feet) in height and the largest is the trilithon in the south west of the horseshoe is almost 7.5 m (24 feet) tall.

This ambitious phase is radiocarbon dated to between 2440 and 2100 BC.

Stonehenge 3 III

Later in the Bronze Age, the bluestones appear to have been re-erected for the first time, although the exact details of this period are still unclear. They were placed within the outer sarsen circle and at this time may have been trimmed in some way. A few have timber working-style cuts in them like the sarsens themselves, suggesting they may have been linked with lintels and part of a larger structure during this phase.

Stonehenge 3 IV (2280 BC to 1930 BC)

This phase saw further rearrangement of the bluestones as they were placed in a circle between the two settings of sarsens and in an oval in the very centre. Some archaeologists argue that some of the bluestones in this period were part of a second group brought from Wales. All the stones were well-spaced uprights without any of the linking lintels inferred in Stonehenge 3 III. The Altar Stone may have been moved within the oval and stood vertically. Although this would seem the most impressive phase of work, Stonehenge 3 IV was rather shabbily built compared to its immediate predecessors, the newly re-installed bluestones were not at all well founded and began to fall over. However, only minor changes were made after this phase. Stonehenge 3 IV dates from 2280 to 1930 BC.

Stonehenge 3 V (2280 BC to 1930 BC)

Soon afterwards, the north eastern section of the Phase 3 IV Bluestone circle was removed, creating a horseshoe-shaped setting termed the Bluestone Horseshoe. This mirrored the shape of the central sarsen Trilithons and dates from 2270 to 1930 BC. This phase is contemporary with the famous Seahenge site in Norfolk.

After the monument (1600 BC on)

Even though the last known construction of Stonehenge was about 1600 BC, and the last known usage of it was during the Iron Age (if not as late as the 7th century), where Roman coins, prehistoric pottery, an unusual bone point and a skeleton of a young male (780-410 cal BC) were found, we have no idea if Stonehenge was in continuous use or exactly how it was used. Notable is the late 7th-6th century BC large arcing Scroll Trench which deepens E-NE towards Heelstone, and the burial of a decapitated Saxon man excavated from Stonehenge dated to the 7th century. The site was known by scholars during the Middle Ages and since then it has been studied and adopted by numerous different groups.