Neanderthals Likely Built These 176,000-Year-Old Underground Ring Structures
Scientists take measurements for the archaeo-magnetic survey in the Bruniquel Cave, where they found near-circular structures made of stalagmites.
Credit: Etienne FABRE - SSAC

About 40,000 years before the appearance of modern man in Europe, Neanderthals in southwestern France were venturing deep into the earth, building some of the earliest complex structures and using fire.

That's according to new research that more precisely dated bizarre cave structures built from stalagmites, or mineral formations that grow upward from the floor of a cave. Scientists discovered about 400 stalagmites and stalagmite sections that were collected and stacked into nearly circular formations about 1,100 feet (336 meters) from the entrance of Bruniquel Cave, which was discovered in 1990.