Well of Barhout ("Well of Hell") in Al-Mahra, Yemen

[Astronuc]

Another interesting and unique feature on the Earth's surface is the Well of Barhout. It is described as a sink hole, but looks more like a cavern, in the middle of the desert. https://en.wikipedia.org/wiki/Well_of_Barhout
Location: Al-Mahra, near Hadhramaut, Yemen
Coordinates: 17°20′25″N, 52°26′38″E
Depth: 100–200 m (330–660 ft)
Length: 30 m (98 ft)
https://en.wikipedia.org/wiki/Hadhramaut

Apparently, there are noxious gases emanating from the cavern and little oxygen in the depths. Origins are unknown/uncertainty.

The Smithsonian Volcanic Program reports an old volcanic field in Hadhramaut region. https://volcano.si.edu/volcano.cfm?vn=231180
The last eruption is unknown, so perhaps it was prehistoric.

https://phys.org/news/2021-06-danger-demons-yemen-mysterious-hell.html
https://news.yahoo.com/well-hell-gaping-desert-hole-122159139.html
https://www.france24.com/en/live-news/20210621-danger-and-demons-yemen-s-mysterious-well-of-hell

Maybe an extinct volcano?

 

[anorlunda]

It is described as a sink hole, but looks more like a cavern, in the middle of the desert.

Sink holes are often caused by collapsed caverns.

 

[AlexTheParticle]

Wow, this is so fascinating! I had never heard of the Well of Barhout before. It's amazing how there are still unknown and mysterious places on our planet. The fact that it is described as a sinkhole but looks more like a cavern is definitely intriguing. And the fact that there are noxious gases and little oxygen in the depths adds to the mystery. I wonder if there have been any attempts to explore the well and its surroundings. It would be interesting to know the origins of this unique feature.

I did some research and found that the Smithsonian Volcanic Program reports an old volcanic field in the Hadhramaut region, where the Well of Barhout is located. It's possible that the well was formed by a volcanic eruption in the past. However, the last eruption in that area is unknown, so it could have been prehistoric. It's also interesting to note that there are several reports of "danger and demons" associated with the well, which could add to the mystery and intrigue surrounding it.

I also came across some recent news articles about the Well of Barhout, including one from Phys.org and Yahoo News. It seems like there is a lot of interest and attention being given to this mysterious feature. I hope that more research and exploration can be done in the future to uncover the secrets of the Well of Barhout. It's definitely a unique and intriguing place on our planet.