Saudi Arabia has discovered 400 mysterious ancient stone buildings.

Mysterious stone structures have been found in Saudi Arabia, which archaeologists call "gates" because they are roughly similar to old-fashioned field gates. According to archaeologists, Google Earth has discovered about 400 mysterious stone structures dating back thousands of years in Saudi Arabia, some of which are wall-like structures covering ancient lava domes.

Many stone walls, which archaeologists call "gates" because they are similar to the field gates above, were found in a cluster in a region called Harrat Khaybar in the middle and west of Saudi Arabia.

Archaeologists involved in this study are not sure about the purpose of these doors, or even the exact age. [See the mysterious map of Saudi Arabia's stone structure. ]

Those long and mysterious ones were mainly discovered through satellite images. The researchers found that some gates were actually located on the side of the volcanic dome that once spewed basalt lava.

The gate is made of stone and the walls are rough and low. David Kennedy, a professor at the University of Western Australia, wrote in a paper that this paper will be published in the June issue of Archaeology and Epigraphy 165438+. Kennedy pointed out that these gates "seem to be the oldest man-made buildings in the landscape" and added that "there is no obvious explanation for their purpose."

The smallest gate is about 43 feet (13 meters) long, while the longest gate is 1699 feet (5 18 meters), which is longer than the football field in the NFL. Many city gates have multiple stone walls, in some cases, forming a rectangular design; Other gates are called I-shaped gates, with only one stone wall and a pile of stones at each end.

The city gate exists almost exclusively in the desolate and uninhabitable lava field, where there is almost no water and vegetation. It seems to be the least popular place "our species", Kennedy wrote. He pointed out that thousands of years ago, the landscape here was more suitable for human life. Other types of stone structures have been found in these lava areas, such as kites used to hunt animals and wheels named after shapes.

Kennedy said that kites, wheels and other types of stone structures are usually found on these door-like walls, which shows that these stone doors predate these stone structures. Kennedy said that the remains of lava flows are sometimes found at the top of the city gate, which shows that the city gate is older than some lava flows.

Most of the city gates that need field investigation were discovered by satellite investigation, and no archaeological field investigation was carried out. However, in the 1980s, before these volcanic gates were discovered, volcanologists Vic Kemp and John Rewbell drew a map of the Hajaba area in Halat, including a lava dome dotted with volcanic gates and other stone structures. This lava dome is located near a higher lava dome called Jabal Abyad, which is in * * *, meaning "White Mountain".

Kemp said that the lava dome is no longer active, adding that in the past, basalt lava covered some stone structures, including the gate.

We see that young lava in some areas does not have such lava (stone) structure, although it is surrounded by several (stone) structures, "Kemp told Life Science. The photo shows that one of the stone structures is partially covered by hardened lava. Kemp estimated that some gates around the lava dome were built 7000 years ago.

Kennedy said that archaeological site investigation is necessary to determine what these doors are and the exact date.

Travis hern, research assistant of Middle East Archaeological Aerial Photography Archives, wrote articles for The Wall Street Journal; Kennedy also cooperated with members of the desert group, a group of Saudi citizens, who first drew some stone structure maps and visited some sites.

Originally published in Life Science.