Researchers have been trying to unravel the mysteries of Stonehenge for more than eight centuries. Thanks to a hose that was a little too short, and a prolonged drought, scientists were able to make one of the most significant revelations in recent years.

Stonehenge used to be a complete circle.

Back in 2013, as ground dried up on the monument side, scorched spots of grass started to appear where one would expect stones to lie if Stonehenge's partial circle was completed. Local archaeologists were notified about the spots by the groundskeeper to be analyzed.

"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," said Tim Daw to BBC News. "A sudden lightbulb 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."

Stonehenge was most likely constructed in several stages during the Neolithic period. It took a few hundred years to complete somewhere between 3000 BCE to 2000 BCE.

Though Archaeologists have confirmed Daw's suspicions, they said the brief period of time prevented them from reaching a more affirmative conclusion, according to BBC News.

"If these stone holes actually held upright stones then we've got a complete circle," said Susan Greaney, historian with the Stonehenge care-taking and cultural preservation group English Heritage, told the BBC. "It's really significant, and it shows us just how much we still have to learn about Stonehenge."

Future droughts could allow scientists to carry out more examinations.

Their research was published this week in the journal Antiquity.

"Ideally the survey would have differentiated between marks caused by parching, the majority, and those caused by lusher growth," scientists wrote in the paper. "It would have also have graded the marks into 'definitive', 'probable' and 'possible' categories," the study's authors continued. "This was not possible, and the result must therefore be treated with caution."

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