New evidence suggests Stonehenge was once a complete circle
Image: via The Telegraph

It’s been a big week for Stonehenge, with scientists last week revealing they’d found 15 structures buried around the neolithic monument.

And now, after an unseasonably dry summer and a too-short watering hose, archaeologists finally have evidence that Stonehenge's inner ring was once a perfect circle - patches of parched grass where the stones once lay.

Historians have previously performed many excavations and geophysical surveys to find clues of rocks that once closed the inner circle. But the evidence finally came in the form of a ghostly patches of extra dry grass, which archaeologists now believe are the ‘stone holes’ where the remaining bluestones that formed the circle once lay.

Usually the groundkeepers water the grass around the structure regularly during the height of summer, but this year their hose was too short to reach the gap in the inner circle, and the grass dried out.

Worker Tim Daw first spotted the ghostly patches on the ground, as Sarah Knapton, the Science Correspondent for The Telegraph reports.

Daw told The Telegraph:

"I was standing on the public path looking at the grass near the stones and thinking that we needed to find a longer hosepipe to get the parched patches to green up.”

“A sudden light-bulb moment in my head, and I remembered that the marks were where archaeologists had looked without success for signs that there had been stone holes, and that parch marks can signify them.”

“I called my colleague over and he saw them and realised their possible significance as well. Not being archaeologists we called in the professionals to evaluate them.”

Patches of grass may sound somewhat, well, patchy, as far as evidence goes. But, as George Dvorsky reports for io9, researchers have confirmed that archaeological remnants that have been buried in the ground for extended periods are known to affect the rate of grass growth above them - even after they’ve been removed.

In the past, Knapton explains in The Telegraph, heatwaves have revealed the ghostly outlines of Roman forts, the remains of Stone Age monuments and Iron Age earthworks.

Susan Greaney from English Heritage, the governing body that looks after Stonhenge, told Knapton that the find is “really significant, and it shows us just how much we still have to learn about Stonehenge.”