This cave sheltered some of the first known humans 300,000 years ago

In the foothills of Siberia's Altai Mountains lies a cave that contains some of the keys to understanding the earliest humans to walk the Earth. Denisova Cave is the only place in the world where fossils have been found that belong to mysterious ancient humans called Denisovans.

New dating techniques used by two teams of researchers have established a chronological timeline for the cave, extending from 300,000 years ago to about 20,000 years ago. They believe that Denisovans lived in the cave between 287,000 and 55,000 years ago and overlapped with Neanderthal occupation of the cave between 193,000 and 97,000 years ago.