where did the stones of stonehenge come from
Stonehenge The long distance human transport theory was bolstered in 2011 by the discovery of a megalithic bluestone quarry at Craig Rhos-y-felin, near Crymych in Pembrokeshire, which is the most likely place for some of the stones to have been obtained.[27] Other standing stones may well have been small sarsens (sandstone), used later as lintels. The stones, which weighed about two tons, could have been moved by lifting and carrying them on rows of poles and rectangular frameworks of poles, as recorded in China, Japan and India. It is not known whether the stones were taken directly from their quarries to Salisbury Plain or were the result of the removal of a venerated stone circle from Preseli to Salisbury Plain to "merge two sacred centres into one, to unify two politically separate regions, or to legitimise the ancestral identity of migrants moving from one region to another".[27] Each monolith measures around 2 metres (6.6 ft) in height, between 1 and 1.5 m (3.3 and 4.9 ft) wide and around 0.8 metres (2.6 ft) thick. What was to become known as the Altar Stone is almost certainly derived from the Senni Beds, perhaps from 50 miles (80 kilometres) east of Mynydd Preseli in the Brecon Beacons.[27]
Dry stone Terminology varies regionally. When used as field boundaries, dry stone structures often are known as dykes, particularly in Scotland. Dry stone walls are characteristic of upland areas of Britain and Ireland where rock outcrops naturally or large stones exist in quantity in the soil. They are especially abundant in the West of Ireland, particularly Connemara. They may also be found throughout the Mediterranean, including retaining walls used for terracing. Such constructions are common where large stones are plentiful (for example, in The Burren) or conditions are too harsh for hedges capable of retaining livestock to be grown as reliable field boundaries. Many thousands of miles of such walls exist, most of them centuries old.