The mystery shrouding the ancient 'Big Circles' found in the Middle East is beginning to be unravelled following aerial images that reveal details of the huge stone structures.

Images show the 11 stone circles that date back at least 2,000 years across Jordan and Syria. Many have since been destroyed, but the high-resolution images from the Aerial Photographic Archive for Archaeology in the Middle East (APAAME) are providing researchers with more information on their mysterious origins.

All but one of the circles are around 400m in diameter and they appear to have been built as low stone walls with no openings – people would have had to jump over to get inside, LiveScience reports.

Big Circles
The Big Circles were first found in the 1920s APAAME

David Kennedy, professor of classics and ancient history at University of Western Australia and director of APAAME, has now published an article in Zeitschrift für Orient-Archäologie 6 in which he says the Big Circles should be the focus of greater research – another partially completed stone circle was found in Jordan has been found in addition to the known 11.

The circles were first found in the 1920s after being spotted by an aircraft. Since then, they have baffled scientists – nothing is known of them and researchers say they could have even been constructed in prehistoric times before the invention of writing.

Big Circles
One of the Big Circles in Jordan APAAME

Kennedy told the website that the circles being so similar cannot be a coincidence. Many stone circles exist in the Middle East, but the 11 identified are much larger.

He said the circles were not hard to construct and using local rocks, just a small group of people could have been completed in a week. However, the planning would have been more complex, he said: "In the case of those circles that [are] near-precise circles, it would have required at least one person as 'architect'."

Kennedy hypothesised that one person could have tied a rope to a post and walked in a circle.

Big Cirlces
Experts believe the circles could date to prehistoric times APAAME

For their use, one suggestion is that they were used to maintain animal herds, but he discounted this as there is no need for the structure to be circular. Also the idea it could have been used for burial is unlikely, he said.

Many of the circles have now been mostly or completely destroyed, but Kennedy said aerial and satellite images can provide vital information about their history. The team will now continue to excavate the sites in the hope of one day solving the mysteries the Big Circles hold.

big circles
Many of the stone circles have been partially or completely destroyed APAAME