Stonehenge
Stonehenge is a massive stone monument located on a chalky plain north of the modern-day city of Salisbury, England. Research shows that the site has continuously evolved over a period of about 10,000 years. The structure that we call “Stonehenge” was built between roughly 5,000 and 4,000 years ago and that forms just one part of alarger, and highly complex, sacred landscape.
The biggest of Stonehenge’s stones, known as sarsens, are up to 30 feet (9 meters) tall and weigh 25 tons (22.6 metric tons) on average. It is widely believed that they were brought from Marlborough Downs, a distance of 20 miles (32 kilometers) to the north.
Smaller stones, referred to as “bluestones” (they have a bluish tinge when wet or freshly broken), weigh up to 4 tons and come from several different sites in western Wales, having been transported as far as 140 miles (225 km). It’s unknown how people in antiquity moved them that far. Scientists have raised the possibility that during the last ice ageglaciers carried these bluestones closer to the Stonehenge area and the monument’s makers didn’t have to move them all the way from Wales. Water transport through raft is another idea that has been proposed but researchers now question whether this method was viable.
The story of how Stonehenge, and its sacred landscape, was built is evolving rapidly as new archaeological discoveries are made. The IBM Visual and Spatial Technology Centre at the University of Birmingham is using an array of technologies, including ground penetrating radar and magnetometers, to map Stonehenge and its environs. The project has produced an enormous amount of data, which scientists haven’t fully analyzed.
