The archeologists base their theory of Stonehenge’s purpose partly on qualities of bluestones used at the monument. The stones are placed in a double circle with the entrance facing northeast. During the past century, the bluestones were shown to be from the Preseli Mountains in Wales. Their name comes from their color. Some people say the stones appear to be blue when they are wet or cut.

The archeologists note that some bluestones in modern Wales are still part of a healing tradition. In some places, people use water poured over the stones in an effort to cure sickness.

Archeologists Wainwright and Darvill made an important discovery at Stonehenge in 2008. They dug up about 100 pieces of organic material from where the first bluestones were placed. From this discovery, they say the bluestone circle was built about 4,300 years ago.

A number of theories have been proposed to explain how the heavy stones made their way to the Salisbury Plain. Some geologists have suggested that glaciers – huge ice formations – carried the stones. But hundreds of kilometers separate the mountains in Wales from the windy English plain.

Efforts to transport the heavy stones by boat on the river sank the boat. And attempts to row the stones across land showed that it would have taken months to move them a relatively short distance. Some experts, however, note that ancient people had lots of time and may have been more than willing to do the labor.