There is lots of information about Stonehenge on the internet but this is a good website for children — click here […]. See all. Stonehenge Facts! Discover the secrets of this incredible ancient monument…. Then check out our fascinating Stonehenge facts… What is Stonehenge?
When was Stonehenge built? How was Stonehenge built? Brand new discovery! It seems that Stonehenge may have originally been built in Wales! Evidence of a stone circle suspiciously similar to Stonehenge has just been discovered in Wales, very near to the quarry where some of the bluestones originate from. It looks like these huge stones may have stood in Wales for many years, before they were uprooted and dragged to Wiltshire to form the Stonehenge we know today.
Phew — that sounds like hard work! What was Stonehenge used for? But the stones themselves give us a few clues, which have given rise to many different theories… Each year, on 21 June the longest day of the year , the sun always rises over the Heel Stone at Stonehenge — a single large sarsen stone which stands outside of the main monument.
In short, the convergence of these two glaciers acted as a conveyor belt, transporting erratics in a trail leading straight to Stonehenge. But can glaciers form such a linear trail of erratics?
To gain an appreciation for how the convergence of two ice sheets can create a virtual conveyor belt for the transport of erratics, we have to travel to the foothills of the Rocky Mountains in Alberta, Canada. This amazing trail of pebbly quartzite erratics, called the Foothills Erratics Train, can be traced from the forested Macleod River region in Alberta to the United States-Canada border in western Montana kilometers southward.
Over most of its length, the trail is only a few kilometers wide, narrowing to less than one kilometer in some areas. Individual erratics range in size from less than a cubic meter to one rock that has the mass of 10 Stonehenges. The rocks appear to have fallen onto valley glaciers, which carried them into the Foothills Erratics Train via glaciers in the Athabasca River Valley. Normally, mountain glaciers would spread into so-called piedmont lobes where they leave the mountains and spill out onto the plains, dispersing the rocks that they carry in a fan shape.
Indeed, this occurred farther south in the American Rockies during the last glacial maximum about 20, years ago.
The Athabasca Valley Glacier carrying the erratics became a tributary to the Laurentide Ice Sheet and flowed southeastward with it. This parallel flow of two ice streams, maintained by pressure from both sides, is quite analogous to the situation in Wales. As the two ice streams came together, they would have maintained a contact zone as the ice approached its easternmost limit in England.
It is reasonable to believe that the contact zone of ice carrying bluestone erratics — and maybe some other stones from South Wales — would have resulted in an erratics train rather than a fan. Unlike the blocks of the Foothills Erratics Train that fell onto the surface of the glacier from cliffs in the Rocky Mountains, the bluestone erratics train would have been plucked from outcrops and initially transported within the ice.
However, once entrained, the blocks would have been transported relatively high within the body of the glacier see sidebar, p. By using the Canadian Rockies analogy, it suddenly becomes clear how the boulders of Stonehenge could have been deposited in a trail across southwestern England — and thus would have been easy pickings for Neolithic Britons. Why, he asked, did the early builders of Stonehenge choose only exotic stones when they created the first stone circle if Salisbury Plain was littered with a variety of glacially transported rocks, including local sarsen rock types?
This is a good question, to be sure. The problem is, his questions are based upon a false assumption — namely, that we know exactly which stones were used in the early arrangements or settings at Stonehenge. We do not know. In fact, it is probable that these stones were intermingled. The bluestones would have been easy to find by following a trail across a familiar landscape.
The Stonehenge builders probably initially used the closest available blocks and then gathered stones from farther and farther afield, toward the west and maybe the north.
The overriding factor in the rocks' selection appears to have been a comparatively easy hauling distance to the site. Availability apparently trumped suitability. Nothing in the evidence suggests a magical or mystical link between Stonehenge and the Preseli Hills. The builders of Stonehenge probably had no idea where the stones had come from.
As pointed out in recent decades by dissenting archaeologists like Aubrey Burl of Hull College in England and Stephen Briggs of the British Royal Commission on Ancient and Historical Monuments, this same bluestone was used for both the Stonehenge monoliths and for the manufacture of standard axe-heads — suggesting no special regard for it.
The bluestone arrangements at Stonehenge were reorganized many times. This probably reflects the utilitarian fact that the builders never did manage to find enough bluestones to complete the task at hand, whatever that might have been.
Stonehenge may have been a spiritual or magical temple, but the project engineers who designed and built the monument had to address the same practical issues — namely, material sourcing and supply within available labor and material constraints — that any modern construction project faces. Will there ever be a final conclusion to this marvelous, prehistoric mystery? Perhaps not. But evidence from the fields of geology and glaciology is — after decades of neglect — coming to the fore. All rights reserved.
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Click here for all copyright requests. Stonehenge's Mysterious Stones by Brian S. Also see "Stonehenge Built With Balls? For about two decades, Ixer and study co-author Richard Bevins, of the National Museum of Wales, have searched for the origins of the bluestones in outcrops around Wales.
As late as two years ago, the pair thought the blocks couldn't have come from the country—no samples from Welsh outcrops matched the Stonehenge blocks. Take a Stonehenge quiz. But not all of the samples collected over 20 years had yet been prepared for examination under a microscope.
To be absolutely certain, the geologists began slicing up their remaining rocks. The very first one—a chunk of rock collected in Wales 20 years ago—was a perfect match to the Stonehenge bluestones.
The geologists spent the next two years checking a piece of Stonehenge bluestone against other outcrops around Wales. The rocky outcrop fingered by the duo's analysis is called Craig Rhos-y-Felin, which is now located on private land near a sheep farm. Humans could have quarried the site and dragged the blocks on wooden rafts. Or a giant glacier may have chiseled off the blocks and ferried them about a hundred miles kilometers toward Stonehenge, with humans dragging them the rest of the way.
If humans did the digging, archaeologists might detect marks left by tools or some other evidence. But if signs of human quarrying are lacking, the glacier idea might gain the upper hand. But settling the issue, Ixer says, isn't up to geologists such as himself: "I have never betted in my life" and will not start now, he said.
If they can show the rocks were quarried, that would suggest those rocks were transported by man. The origin of the Stonehenge bluestones is described in an upcoming paper in the journal Archaeology in Wales.
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