Evidence for the alternative theory – that they were transported to the vicinity of Stonehenge by a glacier (which would account for the motley mix of rock-type) – is though, at the moment, not overwhelming, and the Professors Timothy Darvill and Geoffrey Wainwright consider the bluestones to be Stonehenge's raison d'être.
They believe the stones were thought to have healing properties, and that Stonehenge was “a prehistoric Lourdes” – a place of pilgrimage, to where people would travel in the hope of being cured.
Most henges contained various types of feature – for instance, arrangements of stones, timbers or pits.
It is generally thought that they were ceremonial centres, where people would gather together to take part in religious rituals and other communal activities.
In about 2500BC, however, Stonehenge entered a period of development during which stones were arranged and rearranged, to eventually produce the monument whose impressive wreckage remains today. The stone settings built at the centre of Stonehenge fall into two categories: those made from bluestones, and those made from ‘sarsens’.
Sarsens are naturally occurring sandstone slabs, and, it is generally believed, they were sourced from the Marlborough Downs, almost 20 miles to the north.The small bluestone circle inside the trilithon horseshoe, assuming there was such a structure, was restyled into an oval.According to the SRP's proposed sequence, the bluestones of the new, larger, circle had, until this time, stood in the Q and R Holes (the previous notion was that they had been removed from the site when the sarsens were installed, only to be brought back at end, to produce a horseshoe setting of bluestones, echoing the sarsen trilithon setting.is Stonehenge, where stones of extraordinary dimensions are raised as columns, and others are fixed above, like lintels of immense portals; and no one has been able to discover by what mechanism such vast masses of stone were elevated, nor for what purpose they were designed.” Stonehenge's first chronicler, Henry of Huntingdon, mused on ‘the how’ and ‘the why’ of its construction, and, nine centuries later, archaeologists are still trying to provide satisfactory answers to those two basic questions.Considerable progress has, however, been made in unravelling Stonehenge's history, and, thanks to Radiocarbon Dating, answering a third important question: ‘the when’.The SRP has, however, questioned the supposed stratigraphic relationship between the bluestone arcs and the sarsens, and suggests that the settings were Aubrey Holes centuries before their first appearance at the henge's centre.The central bluestones underwent subsequent rearrangement (of which more later), and it appears that there were about eighty of them in total.The SRP has found evidence supporting Mike Parker Pearson's theory that Stonehenge was but one component of a larger ritual complex. In 2005, a metalled roadway (Durrington Avenue) connecting the Southern Circle of Durrington Walls to the River Avon was discovered.Whereas Stonehenge and the Avenue were aligned on the axis of the midsummer sunrise and midwinter sunset, the Southern Circle and roadway were aligned on the axis of the midwinter sunrise and midsummer sunset.In about 2500BC, a circle (30 metres in diameter) of thirty sarsen uprights (standing approximately 4 metres above ground level), topped off by a continuous circuit of sarsen lintels, was erected around a horseshoe arrangement (the open end pointing in a The first appearance of bluestones in the middle of the henge – indeed, their first definite appearance anywhere on site – was in a concentric double arc setting.The evidence for this placement is provided by the, so-called, , which lie between the sarsen circle and trilithon horseshoe settings.