Researchers from Australia captured remarkable aerial images of 11 huge stone circles across the Middle East.

The purpose of these stone circles remains unknown, and the structures seem to be built more than 2,000 years ago, according to Live Science. 

Prof. David Kennedy from the University of Western Australia dubbed the ancient stone circles as the "Big Circles."

Each stone measured around 400 meters in diameter, and all 11 of them, coincidentally, had low walls with no openings. Archaeologists had to go into the walls to get inside.

Further analysis of the aerial images and artifacts scattered near the Big Circles imply that the structure could be more than 2,000 years old, and might have been used as a burial site because of the cairns, or rock piles, found.

In another coincidence, researchers found a similar structure in Jordan and Syria, although both have been ruined.

Fortunately, archaeologists Graham Philip and Jennie Bradbury from the Durham University of England were able to examine the circle before it got destroyed 10 years ago to give way for land development. If the Big Circles could have been used for burial, the Syrian circle could have been used as storage for crops and settlements.

There were other circles scattered in the Middle East, although the rest were smaller than the ancient Big Circles.

Kennedy presumed that the stone circles were built using local rocks with 12 people doing one Big Circle in just 7 days by tying the stones in a long rope and pulling it to the ground. The planning might have taken longer because of its accuracy.

"In the case of those circles that [are] near-precise circles, it would have required at least one person as 'architect.' That would also explain the glitches [in the circles] where the land was uneven," Kennedy told Live Science.

Further details of the discovery were published in Zeitschrift für Orient Archäologie.