A mysterious cult that predates Stonehenge

The car was gliding smoothly along the immaculately maintained highway in AlUla, a region in north-western Saudi Arabia, when my driver abruptly veered off the road. "I missed the turning," he said. I looked out of the window in confusion as I couldn't see an obvious bend. "Here," he exclaimed, as the car jolted across basalt rocks to join a barely discernible path into the desert.

We drove into a vast, flat landscape. A bright blue sky enclosed us on all sides and a smattering of white clouds hung low. After a few minutes, we stopped by acircle of stacked stones. I climbed out of the car, waiting to meet Jane McMahon, part of a team of archaeologists from the University of Western Australia that has been working in AlUla since 2018. All around me was an arid plain of grey-black rocks lightly dusted in pink-hued sandThere was something otherworldly about it all: the lack of a single tree or a blade of grass; the stillness of the air that was only occasionally interrupted by a bitter gust of wind that chilled you to the bone.

I'd come here because recent discoveries in AlUla are shining a light on a fascinating period of history in Saudi Arabia. Since the nation only opened for international research a few years ago (and to tourists in 2019), many of its ancient sites are being studied for the first time. While historians are familiar with the ruins of the 2,000-year-old cities Hegra and Dadan and their place on the Incense Route (Hegra's tombs and monuments are a Unesco World Heritage Site), they didn't have much knowledge about the civilisation that came before, until now.

What has been discovered is that spread over AlUla's vast, remote landscape are millennia-old archaeological remains that could change our understanding of prehistory. Work by McMahon and her colleagues is shedding light on some of the earliest stone monuments in world history – predating Stonehenge and the earliest pyramid in Giza.