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 (100 ft) wide at the surface, and it is 112 metres (367 ft) deep.

It was first explored by the Oman Cave Exploration Team (OCET), who reached the bottom on September 15, 2021.

Footage provided to Agence France-Presse (AFP) showed cave formations and grey and lime-green cave pearls, formed by dripping water.

The spelunkers 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 analyzation. A full report of the team's findings will be made available to the public.

More Info: en.m.wikipedia.org