Around 400 mysterious clustered stone structures have been found, via satellite imagery, in an inhospitable region of west-central Saudi Arabia. At present, it’s not clear what they were for, but they’ve been nicknamed “gates” based on their appearance.
Their age is unknown, as are their architects' identities. Either way, according to the University of Western Australia’s ancient history professor David Kennedy, they’re the “oldest man-made structures in the area.”
They’ve been built roughly, and seem to be fairly low. Some are relatively small, extending only around 13 meters (43 feet) across. Others are far larger, with the longest being 518 meters (1,699 feet) from end to end.
The international team behind the research, due to publish its analysis in the journal Arabian Archaeology and Epigraphy next month, has spotted some remarkable details that hint at the purpose and construction timeline of the "gates".
For one thing, the entire area – named Harrat Khaybar – is a volcanic field covered in extremely old lava flows. A few of the gates have even been constructed on top of some of the more prominent, now-extinct lava domes.
The last known eruption dates back to the year 650, and some of the frozen remnants have been placed atop these “gates,” implying that they're at least 1,370 years old. The year 650 eruption at the otherworldly site coincides with the very early spread of Islam around the region. Were the walls built around this time?
Plenty of lava flows predate this, however, so the walls could be much older. It all depends on what the geochronological dating of the lava flows, and maybe even the “gates” themselves, reveals.
For one thing, the researchers explain that other types of stone structures called “kites” – once used to hunt animals – hint that the landscape pre-eruption peak may have been far more habitable to human existence. Tuff cones, volcanic edifices that tend to form near water, also suggest that the area was wetter in the past.
The fact that kites were found on top of these “gates” implies that the mysterious stone walls predate this period of time, which also means they are older than plenty of these lava flows.
Right now, it’s anyone’s guess – and a proper recon of the area, on foot, is needed.
Using satellite imagery to look for hidden geological or archaeological structures that can’t be seen from the ground tends to produce mixed results. Sure, sometimes an ancient, supermassive fire pit that predates Stonehenge, or a volcano-mimicking temple in Peru can be identified – but sometimes, that long-lost Mayan temple turns out to be illegal marijuana fields instead.
Fortunately, this time around, it seems that "space archaeology" has once again hit the jackpot.