Stone Age blueprints are the oldest architectural plans ever found

Architects drew up highly precise plans of vast stone-walled hunting traps 9000 years ago, representing the oldest known architectural plans to scale in human history.

The plans were etched into massive stone tablets that have been recently discovered close to the elaborate traps, known as desert kites, which span such wide distances that their shapes are only recognisable from the sky. The findings confirm that Neolithic humans had an “underestimated mental mastery” of landscapes and space, well before they became literate, says Rémy Crassard at the French National Centre for Scientific Research (CNRS).

“There’s no doubt that these Homo sapiens had the same degree of intelligence that we do, but this is the first time we actually have concrete proof of their spatial perception – in both these gigantic kites and now also in their very precise corresponding plans,” he says. “It shows to what extent this way of thinking was anchored into their culture.”

Kites in Saudi Arabia and Jordan feature funnelling lines up to 5 kilometres long and up to 10 pointed branches leading to pits as much as 4 metres deep. Named by aeroplane pilots who first discovered them from the air in the 1920s and thought they looked like toy kites, the structures probably lured gazelles or other wild prey into narrower parts of the structure where they would get cornered or fall, says Wael Abu-Azizeh at the French Institute for the Near East.

But despite the complexity of these Stone Age structures, the rare artistic representations of them found so far have been nothing more than rough abstract sketches. Scientists believed that the oldest true architectural plans that were at least intended to be to scale dated to Mesopotamian civilisations 2300 years ago.

In March 2015, Crassard and his colleagues accidentally came across an 80-centimetre-tall, 92-kilogram limestone tablet in an excavated campsite near a 9000-year-old kite in Jordan, with detailed architectural plans etched into it. They could hardly believe it, but, even more surprisingly, they stumbled across a second kite plan only three months later, this time etched into a 3.8-metre-tall sandstone boulder that had fallen from a cliff near a pair of 7500-year-old kites in Saudi Arabia.

“These were really emotional moments for us in our scientific careers,” says Crassard. “Finding one was already exceptional, but finding two was even more exceptional. We were yelling and dancing around!”

Recognising similarities with the kites nearby, the researchers used computer modelling to mathematically compare the engraved images with satellite images of 69 kites. They found that the plans etched into stone were “surprisingly realistic and accurate” depictions of actual kites within a distance of 1 to 2 kilometres, says Crassard. The two plans had been created at scales of 1:175 and 1:425 and even included three-dimensional pitting to represent the kites’ pit traps.

The plans might have helped build the huge, complex structures, but they might also have guided hunters to understand how best to use them, says Abu-Azizeh.

That seems like the most plausible explanation, says Sam Smith at Oxford Brookes University, UK, who wasn’t involved in the study. Like football coaches drawing their tactics on a white board, members of the Neolithic community may have used the scale images to communicate with each other about group hunting strategies. “I can easily imagine that these engravings would have formed a vital element of planning,” he says.

The fact that they were engraved in “such a durable medium” suggests they may have been intended to last for future generations, he adds. “New members of the community, or hunting party, would not have any real way to comprehend the kites without depictions such as these,” says Smith.

How these ancient engineers attained such geometric accuracy without modern tools like GPS or a tacheometer is perplexing, says Olivier Barge, also at the CNRS. “We don’t know how they did it.”