Well of Barhout

The Well of Barhout (also nicknamed Well of Hell) is a sink hole in Al-Mahara, Yemen. It has a circular entrance that measures about 30 m wide at the surface, and it is 112 m deep.

Physical features
The opening at the top of the Well of Barhout measures 98 ft across, while the bottom of the sinkhole widens to 380 ft. The sinkhole is 367 ft deep and passes through two layers of rock. The top layer is around 200 ft in thickness. The top layer is porous and permeable and thus allows water to filter down to the second layer which is less permeable, where it flows into the sinkhole, creating four waterfalls each measuring 150 ft in height.

Exploration
It was first explored by the Oman Cave Exploration Team (OCET), who reached the bottom on 15 September 2021. Footage provided to Agence France-Presse (AFP) showed cave formations such as stalagmites and grey and lime-green cave pearls, formed by dripping water. The speleologists also report having found snakes, dead animals, and waterfalls in the cave.

Amateur cave explorers have entered the sinkhole before, but until now nobody was known to have made it all the way to the bottom. Samples of the rocks, soil, water, and dead birds found in the cave were collected for further analysis. A full report of the team's findings will be made available to the public.

Folklore
Local folklore says the cave was created as a prison for jinn, and superstition has it that objects near the hole can be sucked towards it. Some nearby residents think that it is bad luck to even talk about it.